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id=m-programming-guidesencoding-li><a href=/programming-guides/encoding/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-programming-guidesencoding><span>Encoding</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-programming-guidesjson-li><a href=/programming-guides/json/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-programming-guidesjson><span>ProtoJSON Format</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-programming-guidestechniques-li><a href=/programming-guides/techniques/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-programming-guidestechniques><span>Techniques</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-programming-guidesaddons-li><a href=/programming-guides/addons/ title="Third-Party Add-ons" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" 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id=m-programming-guidesserialization-not-canonical><span>Proto Serialization Is Not Canonical</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-programming-guidesnullable-getters-setters-li><a href=/programming-guides/nullable-getters-setters/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-programming-guidesnullable-getters-setters><span>No Nullable Setters/Getters Support</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-programming-guidesbest-practices-li><a href=/programming-guides/best-practices/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-programming-guidesbest-practices><span>Proto Best Practices</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-programming-guidesdos-donts-li><a href=/programming-guides/dos-donts/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-programming-guidesdos-donts><span>Proto Best Practices</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-programming-guidesapi-li><a href=/programming-guides/api/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-programming-guidesapi><span>API Best Practices</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-programming-guides1-1-1-li><a href=/programming-guides/1-1-1/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-programming-guides1-1-1><span>1-1-1 Best Practice</span></a></li></ul></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section with-child" id=m-editions-li><a href=/editions/ class="align-left pl-0 td-sidebar-link td-sidebar-link__section" id=m-editions><span>Protobuf Editions</span></a><ul class="ul-2 foldable"><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-editionsoverview-li><a href=/editions/overview/ title="Protobuf Editions Overview" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-editionsoverview><span>Overview</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-editionsfeatures-li><a href=/editions/features/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-editionsfeatures><span>Feature Settings for Editions</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-editionsimplementation-li><a href=/editions/implementation/ class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-editionsimplementation><span>Implementing Editions Support</span></a></li></ul></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section with-child" id=m-getting-started-li><a href=/getting-started/ class="align-left pl-0 td-sidebar-link td-sidebar-link__section" id=m-getting-started><span>Tutorials</span></a><ul class="ul-2 foldable"><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-getting-startedcpptutorial-li><a href=/getting-started/cpptutorial/ title="Protocol Buffer Basics: C++" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-getting-startedcpptutorial><span>C++</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-getting-startedcsharptutorial-li><a href=/getting-started/csharptutorial/ title="Protocol Buffer Basics: C#" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-getting-startedcsharptutorial><span>C#</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-getting-starteddarttutorial-li><a href=/getting-started/darttutorial/ title="Protocol Buffer Basics: Dart" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-getting-starteddarttutorial><span>Dart</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-getting-startedgotutorial-li><a href=/getting-started/gotutorial/ title="Protocol Buffer Basics: Go" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-getting-startedgotutorial><span>Go</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-getting-startedjavatutorial-li><a href=/getting-started/javatutorial/ title="Protocol Buffer Basics: Java" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-getting-startedjavatutorial><span>Java</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" id=m-getting-startedkotlintutorial-li><a href=/getting-started/kotlintutorial/ title="Protocol Buffer Basics: Kotlin" class="align-left pl-0 td-sidebar-link td-sidebar-link__page" id=m-getting-startedkotlintutorial><span>Kotlin</span></a></li><li class="td-sidebar-nav__section-title td-sidebar-nav__section without-child" 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buffers.</div><header class=article-meta></header><div class=section-index><hr class=panel-line><div class=entry><h5><a href=/reference/protobuf/edition-2023-spec/>Protocol Buffers Edition 2023 Language Specification</a></h5><p>Language specification reference for edition 2023 of the Protocol Buffers language.</p></div><div class=entry><h5><a href=/reference/protobuf/proto2-spec/>Protocol Buffers Version 2 Language Specification</a></h5><p>Language specification reference for version 2 of the Protocol Buffers language (proto2).</p></div><div class=entry><h5><a href=/reference/protobuf/proto3-spec/>Protocol Buffers Version 3 Language Specification</a></h5><p>Language specification reference for version 3 of the Protocol Buffers language (proto3).</p></div><div class=entry><h5><a href=/reference/protobuf/textformat-spec/>Text Format Language Specification</a></h5><p>The protocol buffer Text Format Language specifies a syntax for representation of protobuf data in text form, which is 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