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156 <h2>About this documentation<span><a class="mark" href="#documentation_about_this_documentation" id="documentation_about_this_documentation">#</a></span></h2> 157 158 159<p>Welcome to the official API reference documentation for Node.js!</p> 160<p>Node.js is a JavaScript runtime built on the <a href="https://v8.dev/">V8 JavaScript engine</a>.</p> 161<section><h3>Contributing<span><a class="mark" href="#documentation_contributing" id="documentation_contributing">#</a></span></h3> 162<p>Report errors in this documentation in <a href="https://github.com/nodejs/node/issues/new">the issue tracker</a>. See 163<a href="https://github.com/nodejs/node/blob/HEAD/CONTRIBUTING.md">the contributing guide</a> for directions on how to submit pull requests.</p> 164</section><section><h3>Stability index<span><a class="mark" href="#documentation_stability_index" id="documentation_stability_index">#</a></span></h3> 165 166<p>Throughout the documentation are indications of a section's stability. Some APIs 167are so proven and so relied upon that they are unlikely to ever change at all. 168Others are brand new and experimental, or known to be hazardous.</p> 169<p>The stability indices are as follows:</p> 170<p></p><div class="api_stability api_stability_0">Stability: 0 - Deprecated. The feature may emit warnings. Backward 171compatibility is not guaranteed.</div><p></p> 172<!-- separator --> 173<p></p><div class="api_stability api_stability_1">Stability: 1 - Experimental. The feature is not subject to 174<a href="https://semver.org/">Semantic Versioning</a> rules. Non-backward compatible changes or removal may 175occur in any future release. Use of the feature is not recommended in 176production environments.</div><p></p> 177<!-- separator --> 178<p></p><div class="api_stability api_stability_2">Stability: 2 - Stable. Compatibility with the npm ecosystem is a high 179priority.</div><p></p> 180<!-- separator --> 181<p></p><div class="api_stability api_stability_3">Stability: 3 - Legacy. The feature is no longer recommended for use. While it 182likely will not be removed, and is still covered by semantic-versioning 183guarantees, use of the feature should be avoided.</div><p></p> 184<p>Use caution when making use of Experimental features, particularly within 185modules. Users may not be aware that experimental features are being used. 186Bugs or behavior changes may surprise users when Experimental API 187modifications occur. To avoid surprises, use of an Experimental feature may need 188a command-line flag. Experimental features may also emit a <a href="process.html#process_event_warning">warning</a>.</p> 189</section><section><h3>Stability overview<span><a class="mark" href="#documentation_stability_overview" id="documentation_stability_overview">#</a></span></h3> 190<!-- STABILITY_OVERVIEW_SLOT_BEGIN --><table><thead><tr><th>API</th><th>Stability</th></tr></thead><tbody><tr><td class="module_stability"><a href="assert.html">assert</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="async_hooks.html">async_hooks</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="buffer.html">buffer</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="child_process.html">child_process</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="cluster.html">cluster</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="console.html">console</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="crypto.html">crypto</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="dgram.html">dgram</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="diagnostics_channel.html">diagnostics_channel</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="dns.html">dns</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="domain.html">domain</a></td><td class="api_stability api_stability_0">(0) Deprecated</td></tr><tr><td class="module_stability"><a href="fs.html">fs</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="http.html">http</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="http2.html">http/2</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="https.html">https</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="inspector.html">inspector</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="modules.html">module</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="os.html">os</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="path.html">path</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="perf_hooks.html">performance_measurement_apis</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="punycode.html">punycode</a></td><td class="api_stability api_stability_0">(0) Deprecated</td></tr><tr><td class="module_stability"><a href="querystring.html">querystring</a></td><td class="api_stability api_stability_3">(3) Legacy</td></tr><tr><td class="module_stability"><a href="readline.html">readline</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="repl.html">repl</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="stream.html">stream</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="string_decoder.html">string_decoder</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="timers.html">timers</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="tls.html">tls_(ssl)</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="tracing.html">trace_events</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="tty.html">tty</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="url.html">url</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="util.html">util</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="vm.html">vm</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="wasi.html">webassembly_system_interface_(wasi)</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="worker_threads.html">worker_threads</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="zlib.html">zlib</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr></tbody></table><!-- STABILITY_OVERVIEW_SLOT_END --> 191</section><section><h3>JSON output<span><a class="mark" href="#documentation_json_output" id="documentation_json_output">#</a></span></h3> 192<div class="api_metadata"> 193<span>Added in: v0.6.12</span> 194</div> 195<p>Every <code>.html</code> document has a corresponding <code>.json</code> document. This is for IDEs 196and other utilities that consume the documentation.</p> 197</section><section><h3>System calls and man pages<span><a class="mark" href="#documentation_system_calls_and_man_pages" id="documentation_system_calls_and_man_pages">#</a></span></h3> 198<p>Node.js functions which wrap a system call will document that. The docs link 199to the corresponding man pages which describe how the system call works.</p> 200<p>Most Unix system calls have Windows analogues. Still, behavior differences may 201be unavoidable.</p></section> 202 <!-- API END --> 203 </div> 204 </div> 205 </div> 206 <script> 207 'use strict'; 208 { 209 const kCustomPreference = 'customDarkTheme'; 210 const userSettings = sessionStorage.getItem(kCustomPreference); 211 const themeToggleButton = document.getElementById('theme-toggle-btn'); 212 if (userSettings === null && window.matchMedia) { 213 const mq = window.matchMedia('(prefers-color-scheme: dark)'); 214 if ('onchange' in mq) { 215 function mqChangeListener(e) { 216 document.body.classList.toggle('dark-mode', e.matches); 217 } 218 mq.addEventListener('change', mqChangeListener); 219 if (themeToggleButton) { 220 themeToggleButton.addEventListener('click', function() { 221 mq.removeEventListener('change', mqChangeListener); 222 }, { once: true }); 223 } 224 } 225 if (mq.matches) { 226 document.body.classList.add('dark-mode'); 227 } 228 } else if (userSettings === 'true') { 229 document.body.classList.add('dark-mode'); 230 } 231 if (themeToggleButton) { 232 themeToggleButton.hidden = false; 233 themeToggleButton.addEventListener('click', function() { 234 sessionStorage.setItem( 235 kCustomPreference, 236 document.body.classList.toggle('dark-mode') 237 ); 238 }); 239 } 240 } 241 </script> 242</body> 243</html> 244