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interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/%C4%B0nformasiyan%C4%B1n_gizl%C9%99dilm%C9%99si" title="İnformasiyanın gizlədilməsi – Azerbaijani" lang="az" hreflang="az" data-title="İnformasiyanın gizlədilməsi" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Ocultaci%C3%B3_d%27informaci%C3%B3" title="Ocultació d'informació – Catalan" lang="ca" hreflang="ca" data-title="Ocultació d'informació" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Ocultaci%C3%B3n_de_informaci%C3%B3n" title="Ocultación de información – Spanish" lang="es" hreflang="es" data-title="Ocultación de información" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%86%D9%87%D8%A7%D9%86%E2%80%8C%D8%B3%D8%A7%D8%B2%DB%8C_%D8%A7%D8%B7%D9%84%D8%A7%D8%B9%D8%A7%D8%AA" title="نهان‌سازی اطلاعات – Persian" lang="fa" hreflang="fa" data-title="نهان‌سازی اطلاعات" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Masquage_de_l%27information" title="Masquage de l'information – French" lang="fr" hreflang="fr" data-title="Masquage de l'information" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a 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interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%A1%D0%BE%D0%BA%D1%80%D1%8B%D1%82%D0%B8%D0%B5_(%D0%BF%D1%80%D0%BE%D0%B3%D1%80%D0%B0%D0%BC%D0%BC%D0%B8%D1%80%D0%BE%D0%B2%D0%B0%D0%BD%D0%B8%D0%B5)" title="Сокрытие (программирование) – Russian" lang="ru" hreflang="ru" data-title="Сокрытие (программирование)" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E8%B3%87%E8%A8%8A%E9%9A%B1%E8%97%8F_(%E8%BB%9F%E4%BB%B6%E5%B7%A5%E7%A8%8B)" title="資訊隱藏 (軟件工程) – Cantonese" lang="yue" hreflang="yue" data-title="資訊隱藏 (軟件工程)" data-language-autonym="粵語" data-language-local-name="Cantonese" class="interlanguage-link-target"><span>粵語</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a 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<div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"><span class="mw-redirectedfrom">(Redirected from <a href="/w/index.php?title=Data_hiding&redirect=no" class="mw-redirect" title="Data hiding">Data hiding</a>)</span></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Principle of computer program design</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">This article is about the computer programming concept. For the practice of hiding data in a message or file, see <a href="/wiki/Steganography" title="Steganography">Steganography</a>. For data encryption, see <a href="/wiki/Cryptography" title="Cryptography">Cryptography</a>.</div> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-More_citations_needed plainlinks metadata ambox ambox-content ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Information_hiding" title="Special:EditPage/Information hiding">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Information+hiding%22">"Information hiding"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Information+hiding%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Information+hiding%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Information+hiding%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Information+hiding%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Information+hiding%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">November 2008</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p>In <a href="/wiki/Computer_science" title="Computer science">computer science</a>, <b>information hiding</b> is the principle of segregation of the <i>design decisions</i> in a <a href="/wiki/Computer_program" title="Computer program">computer program</a> that are most likely to change, thus protecting other parts of the program from extensive modification if the design decision is changed. The protection involves providing a stable <a href="/wiki/Interface_(computer_science)" class="mw-redirect" title="Interface (computer science)">interface</a> which protects the remainder of the program from the implementation (whose details are likely to change). Written in another way, information hiding is the ability to prevent certain aspects of a <a href="/wiki/Class_(computer_science)" class="mw-redirect" title="Class (computer science)">class</a> or <a href="/wiki/Software_component" title="Software component">software component</a> from being accessible to its <a href="/wiki/Client_(computing)" title="Client (computing)">clients</a>, using either programming language features (like private variables) or an explicit exporting policy. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Overview">Overview</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Information_hiding&action=edit&section=1" title="Edit section: Overview"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The term <i>encapsulation</i> is often used interchangeably with information hiding. Not all agree on the distinctions between the two, though; one may think of information hiding as being the principle and encapsulation being the technique. A software module hides information by encapsulating the information into a module or other construct which presents an interface.<sup id="cite_ref-not_encaps_1-0" class="reference"><a href="#cite_note-not_encaps-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>A common use of information hiding is to hide the physical storage layout for data so that if it is changed, the change is restricted to a small subset of the total program. For example, if a three-dimensional point (<span class="texhtml mvar" style="font-style:italic;">x</span>, <span class="texhtml mvar" style="font-style:italic;">y</span>, <span class="texhtml mvar" style="font-style:italic;">z</span>) is represented in a program with three <a href="/wiki/Floating-point" class="mw-redirect" title="Floating-point">floating-point</a> <a href="/wiki/Scalar_(computing)" class="mw-redirect" title="Scalar (computing)">scalar</a> variables and later, the representation is changed to a single <a href="/wiki/Array_data_structure" class="mw-redirect" title="Array data structure">array</a> variable of size three, a module designed with information hiding in mind would protect the remainder of the program from such a change. </p><p>In <a href="/wiki/Object-oriented_programming" title="Object-oriented programming">object-oriented programming</a>, information hiding (by way of <a href="/wiki/Nesting_(computing)" title="Nesting (computing)">nesting</a> of types) reduces software development risk by shifting the code's <a href="/wiki/Dependency_(computer_science)" class="mw-redirect" title="Dependency (computer science)">dependency</a> on an uncertain implementation (design decision) onto a well-defined <a href="/wiki/Interface_(computer_science)" class="mw-redirect" title="Interface (computer science)">interface</a>. Clients of the interface perform operations purely through the interface, so, if the implementation changes, the clients do not have to change. </p> <div class="mw-heading mw-heading2"><h2 id="Encapsulation">Encapsulation</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Information_hiding&action=edit&section=2" title="Edit section: Encapsulation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Encapsulation_(computer_programming)" title="Encapsulation (computer programming)">Encapsulation (computer programming)</a></div> <p>In his book on <a href="/wiki/Object-oriented_design" class="mw-redirect" title="Object-oriented design">object-oriented design</a>, <a href="/wiki/Grady_Booch" title="Grady Booch">Grady Booch</a> defined encapsulation as "the process of compartmentalizing the elements of an abstraction that constitute its structure and behavior; encapsulation serves to separate the contractual interface of an abstraction and its implementation."<sup id="cite_ref-Booch_2-0" class="reference"><a href="#cite_note-Booch-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>The purpose is to achieve the potential for change: the internal mechanisms of the component can be improved without impact on other components, or the component can be replaced with a different one that supports the same public interface. Encapsulation also protects the integrity of the component, by preventing users from setting the internal data of the component into an invalid or inconsistent state. Another benefit of encapsulation is that it reduces system complexity and thus increases robustness, by limiting the interdependencies between software components.<sup id="cite_ref-Booch_2-1" class="reference"><a href="#cite_note-Booch-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>In this sense, the idea of encapsulation is more general than how it is applied in object-oriented programming. For example, a relational database is encapsulated in the sense that its only public interface is a <a href="/wiki/Query_language" title="Query language">query language</a> (such as <a href="/wiki/SQL" title="SQL">SQL</a>), which hides all the internal machinery and data structures of the database management system. As such, encapsulation is a core principle of good software architecture, at every level of granularity. </p><p>Encapsulating software behind an interface allows the construction of objects that mimic the behavior and interactions of objects in the real world. For example, a simple digital alarm clock is a real-world object that a <a href="https://en.wiktionary.org/wiki/layperson" class="extiw" title="wikt:layperson">layperson</a> (nonexpert) can use and understand. They can understand what the alarm clock does, and how to use it through the provided interface (buttons and screen), without having to understand every part inside of the clock. Similarly, if the clock were replaced by a different model, the layperson could continue to use it in the same way, provided that the interface works the same. </p><p>In the more concrete setting of an object-oriented programming language, the notion is used to mean either an information hiding mechanism, a bundling mechanism, or the combination of the two. (See <a href="/wiki/Encapsulation_(object-oriented_programming)" class="mw-redirect" title="Encapsulation (object-oriented programming)">Encapsulation (object-oriented programming)</a> for details.) </p> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Information_hiding&action=edit&section=3" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The concept of information hiding was first described by <a href="/wiki/David_Parnas" title="David Parnas">David Parnas</a> in 1972.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Before then, modularity was discussed by Richard Gauthier and Stephen Pont in their 1970 book <i>Designing Systems Programs</i> although <a href="/wiki/Modular_programming" title="Modular programming">modular programming</a> itself had been used at many commercial sites for many years previously – especially in <a href="/wiki/I/O" class="mw-redirect" title="I/O">I/O</a> <a href="/wiki/Sub-system" class="mw-redirect" title="Sub-system">sub-systems</a> and <a href="/wiki/Software_library" class="mw-redirect" title="Software library">software libraries</a> – without acquiring the 'information hiding' tag – but for similar reasons, as well as the more obvious <a href="/wiki/Code_reuse" title="Code reuse">code reuse</a> reason. <sup class="noprint Inline-Template" style="margin-left:0.1em; white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Please_clarify" title="Wikipedia:Please clarify"><span title="See MOS:NOTRIPLEDASH (October 2022)">clarification needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading2"><h2 id="Example">Example</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Information_hiding&action=edit&section=4" title="Edit section: Example"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Information hiding serves as an effective criterion for dividing any piece of equipment, software, or hardware, into modules of functionality. For instance, a car is a complex piece of equipment. In order to make the design, manufacturing, and maintenance of a car reasonable, the complex piece of equipment is divided into <a href="/wiki/Module_(programming)" class="mw-redirect" title="Module (programming)">modules</a> with particular interfaces hiding design decisions. By designing a car in this fashion, a car manufacturer can also offer various options while still having a vehicle that is economical to manufacture. </p><p>For instance, a car manufacturer may have a luxury version of the car as well as a standard version. The luxury version comes with a more powerful engine than the standard version. The engineers designing the two different car engines, one for the luxury version and one for the standard version, provide the same interface for both engines. Both engines fit into the engine bay of the car which is the same between both versions. Both engines fit the same transmission, the same engine mounts, and the same controls. The differences in the engines are that the more powerful luxury version has a larger displacement with a fuel injection system that is programmed to provide the fuel-air mixture that the larger displacement engine requires. </p><p>In addition to the more powerful engine, the luxury version may also offer other options such as a better radio with CD player, more comfortable seats, a better suspension system with wider tires, and different paint colors. With all of these changes, most of the car is the same between the standard version and the luxury version. The radio with CD player is a module that replaces the standard radio, also a module, in the luxury model. The more comfortable seats are installed into the same seat mounts as the standard types of seats. Whether the seats are leather or plastic, or offer lumbar support or not, does not matter. </p><p>The engineers design the car by dividing the task up into pieces of work that are assigned to teams. Each team then designs their <a href="/wiki/Software_componentry" class="mw-redirect" title="Software componentry">component</a> to a particular standard or interface which allows the team flexibility in the design of the component while at the same time ensuring that all of the components will fit together. </p><p>Motor vehicle manufacturers frequently use the same core structure for several different models, in part as a cost-control measure. Such a "<a href="/wiki/Automobile_platform" class="mw-redirect" title="Automobile platform">platform</a>" also provides an example of information hiding, since the floorplan can be built without knowing whether it is to be used in a sedan or a hatchback. </p><p>As can be seen by this example, information hiding provides flexibility. This flexibility allows a programmer to modify the functionality of a computer program during normal evolution as the computer program is changed to better fit the needs of users. When a computer program is well designed, decomposing the source code solution into modules using the principle of information hiding, evolutionary changes are much easier because the changes typically are local rather than global changes. </p><p>Cars provide another example of this in how they interface with drivers. They present a standard interface (pedals, wheel, shifter, signals, gauges, etc.) on which people are trained and licensed. Thus, people only have to learn to drive a car; they don't need to learn a completely different way of driving every time they drive a new model. (Granted, there are manual and automatic transmissions and other such differences, but on the whole, cars maintain a unified interface.) </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Information_hiding&action=edit&section=5" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Implementation_inheritance" class="mw-redirect" title="Implementation inheritance">Implementation inheritance</a></li> <li><a href="/wiki/Inheritance_semantics" class="mw-redirect" title="Inheritance semantics">Inheritance semantics</a></li> <li><a href="/wiki/Modularity_(programming)" class="mw-redirect" title="Modularity (programming)">Modularity (programming)</a></li> <li><a href="/wiki/Opaque_data_type" title="Opaque data type">Opaque data type</a></li> <li><a href="/wiki/Virtual_inheritance" title="Virtual inheritance">Virtual inheritance</a></li> <li><a href="/wiki/Transparency_(human%E2%80%93computer_interaction)" title="Transparency (human–computer interaction)">Transparency (human–computer interaction)</a></li> <li><a href="/wiki/Scope_(programming)" class="mw-redirect" title="Scope (programming)">Scope (programming)</a></li> <li><a href="/wiki/Compartmentalization_(information_security)" title="Compartmentalization (information security)">Compartmentalization (information security)</a></li> <li><a href="/wiki/Law_of_Demeter" title="Law of Demeter">Law of Demeter</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Information_hiding&action=edit&section=6" title="Edit section: Notes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-not_encaps-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-not_encaps_1-0">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFRogers2001" class="citation web cs1">Rogers, Wm. Paul (18 May 2001). <a rel="nofollow" class="external text" href="https://www.infoworld.com/article/2075271/encapsulation-is-not-information-hiding.html">"Encapsulation is not information hiding"</a>. <i><a href="/wiki/JavaWorld" class="mw-redirect" title="JavaWorld">JavaWorld</a></i><span class="reference-accessdate">. Retrieved <span class="nowrap">2020-07-20</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=JavaWorld&rft.atitle=Encapsulation+is+not+information+hiding&rft.date=2001-05-18&rft.aulast=Rogers&rft.aufirst=Wm.+Paul&rft_id=https%3A%2F%2Fwww.infoworld.com%2Farticle%2F2075271%2Fencapsulation-is-not-information-hiding.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AInformation+hiding" class="Z3988"></span></span> </li> <li id="cite_note-Booch-2"><span class="mw-cite-backlink">^ <a href="#cite_ref-Booch_2-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Booch_2-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBooch2007" class="citation book cs1">Booch, Grady (2007). <i>Object-Oriented Analysis and Design with Applications</i>. Addison-Wesley. pp. 51–52. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-201-89551-3" title="Special:BookSources/978-0-201-89551-3"><bdi>978-0-201-89551-3</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Object-Oriented+Analysis+and+Design+with+Applications&rft.pages=51-52&rft.pub=Addison-Wesley&rft.date=2007&rft.isbn=978-0-201-89551-3&rft.aulast=Booch&rft.aufirst=Grady&rfr_id=info%3Asid%2Fen.wikipedia.org%3AInformation+hiding" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFParnas1972" class="citation journal cs1"><a href="/wiki/David_Lorge_Parnas" class="mw-redirect" title="David Lorge Parnas">Parnas, David L.</a> (1972). <a rel="nofollow" class="external text" href="https://doi.org/10.1145%2F361598.361623">"On the Criteria To Be Used in Decomposing Systems into Modules"</a>. <i><a href="/wiki/Communications_of_the_ACM" title="Communications of the ACM">Communications of the ACM</a></i>. <b>15</b> (12): 1053–58. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1145%2F361598.361623">10.1145/361598.361623</a></span>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:53856438">53856438</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Communications+of+the+ACM&rft.atitle=On+the+Criteria+To+Be+Used+in+Decomposing+Systems+into+Modules&rft.volume=15&rft.issue=12&rft.pages=1053-58&rft.date=1972&rft_id=info%3Adoi%2F10.1145%2F361598.361623&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A53856438%23id-name%3DS2CID&rft.aulast=Parnas&rft.aufirst=David+L.&rft_id=https%3A%2F%2Fdoi.org%2F10.1145%252F361598.361623&rfr_id=info%3Asid%2Fen.wikipedia.org%3AInformation+hiding" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFScott2009" class="citation book cs1"><a href="/wiki/Michael_L._Scott" title="Michael L. Scott">Scott, Michael L.</a> (2009) [2000]. Broy, Manfred; Denert, Ernst (eds.). <a rel="nofollow" class="external text" href="https://www.cs.rochester.edu/~scott/pragmatics/"><i>Programming Language Pragmatics</i></a> (Third ed.). Morgan Kaufmann Publishers. p. 173. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-3-642-59412-0">10.1007/978-3-642-59412-0</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-3-540-43081-0" title="Special:BookSources/978-3-540-43081-0"><bdi>978-3-540-43081-0</bdi></a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:2698265">2698265</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Programming+Language+Pragmatics&rft.pages=173&rft.edition=Third&rft.pub=Morgan+Kaufmann+Publishers&rft.date=2009&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A2698265%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1007%2F978-3-642-59412-0&rft.isbn=978-3-540-43081-0&rft.aulast=Scott&rft.aufirst=Michael+L.&rft_id=https%3A%2F%2Fwww.cs.rochester.edu%2F~scott%2Fpragmatics%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AInformation+hiding" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Information_hiding&action=edit&section=7" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239549316">.mw-parser-output .refbegin{margin-bottom:0.5em}.mw-parser-output .refbegin-hanging-indents>ul{margin-left:0}.mw-parser-output .refbegin-hanging-indents>ul>li{margin-left:0;padding-left:3.2em;text-indent:-3.2em}.mw-parser-output .refbegin-hanging-indents ul,.mw-parser-output .refbegin-hanging-indents ul li{list-style:none}@media(max-width:720px){.mw-parser-output .refbegin-hanging-indents>ul>li{padding-left:1.6em;text-indent:-1.6em}}.mw-parser-output .refbegin-columns{margin-top:0.3em}.mw-parser-output .refbegin-columns ul{margin-top:0}.mw-parser-output .refbegin-columns li{page-break-inside:avoid;break-inside:avoid-column}@media screen{.mw-parser-output .refbegin{font-size:90%}}</style><div class="refbegin" style=""> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFParnas1971" class="citation conference cs1"><a href="/wiki/David_Lorge_Parnas" class="mw-redirect" title="David Lorge Parnas">Parnas, David L.</a> (1971). <a rel="nofollow" class="external text" href="https://cseweb.ucsd.edu/~wgg/CSE218/Parnas-IFIP71-information-distribution.PDF">"Information Distribution Aspects of Design Methodology"</a> <span class="cs1-format">(PDF)</span>. In Charles V. Freiman and John E. Griffith and Jack L. Rosenfeld (ed.). <i>Information Processing, Proceedings of IFIP Congress 1971, Volume 1 - Foundations and Systems, Ljubljana, Yugoslavia, August 23–28, 1971</i>. IFIP Congress 1971. Vol. 1. North-Holland. pp. 339–344. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1184%2FR1%2F6606470.V1">10.1184/R1/6606470.V1</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=Information+Distribution+Aspects+of+Design+Methodology&rft.btitle=Information+Processing%2C+Proceedings+of+IFIP+Congress+1971%2C+Volume+1+-+Foundations+and+Systems%2C+Ljubljana%2C+Yugoslavia%2C+August+23%E2%80%9328%2C+1971&rft.pages=339-344&rft.pub=North-Holland&rft.date=1971&rft_id=info%3Adoi%2F10.1184%2FR1%2F6606470.V1&rft.aulast=Parnas&rft.aufirst=David+L.&rft_id=https%3A%2F%2Fcseweb.ucsd.edu%2F~wgg%2FCSE218%2FParnas-IFIP71-information-distribution.PDF&rfr_id=info%3Asid%2Fen.wikipedia.org%3AInformation+hiding" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFParnas2002" class="citation book cs1"><a href="/wiki/David_Lorge_Parnas" class="mw-redirect" title="David Lorge Parnas">Parnas, David L.</a> (2002). "The Secret History of Information Hiding". In Manfred Broy and Ernst Denert (ed.). <a rel="nofollow" class="external text" href="https://www.springer.com/gp/book/9783540430810"><i>Software Pioneers</i></a>. Springer-Verlag Berlin Heidelberg. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-12-374514-9" title="Special:BookSources/978-0-12-374514-9"><bdi>978-0-12-374514-9</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=The+Secret+History+of+Information+Hiding&rft.btitle=Software+Pioneers&rft.pub=Springer-Verlag+Berlin+Heidelberg&rft.date=2002&rft.isbn=978-0-12-374514-9&rft.aulast=Parnas&rft.aufirst=David+L.&rft_id=https%3A%2F%2Fwww.springer.com%2Fgp%2Fbook%2F9783540430810&rfr_id=info%3Asid%2Fen.wikipedia.org%3AInformation+hiding" class="Z3988"></span></li></ul> </div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Information_hiding&oldid=1227778952">https://en.wikipedia.org/w/index.php?title=Information_hiding&oldid=1227778952</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Object-oriented_programming" title="Category:Object-oriented programming">Object-oriented programming</a></li><li><a href="/wiki/Category:Programming_principles" title="Category:Programming principles">Programming principles</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_is_different_from_Wikidata" title="Category:Short description is different from Wikidata">Short description is different from Wikidata</a></li><li><a href="/wiki/Category:Articles_needing_additional_references_from_November_2008" title="Category:Articles needing additional references from November 2008">Articles needing additional references from November 2008</a></li><li><a href="/wiki/Category:All_articles_needing_additional_references" title="Category:All articles needing additional references">All articles needing additional references</a></li><li><a href="/wiki/Category:Wikipedia_articles_needing_clarification_from_October_2022" title="Category:Wikipedia articles needing clarification from October 2022">Wikipedia articles needing clarification from October 2022</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 7 June 2024, at 19:04<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. 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