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content/20201113091424-javascript_prototypes.md

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+---
+id: fd03be0e-a4c0-421f-9dd7-1bddc9dece65
+title: JavaScript Prototypes
+---
+
+# Description
+
+A prototype can be seen as an [object](20200826201605-objects) another
+object extends.
+
+# Syntax
+
+``` javascript
+let protoRabbit = {
+  speak(line) {
+    console.log(`The ${this.type} rabbit says '${line}'`); // : The killer rabbit says 'SKREEEE!'
+  },
+};
+let killerRabbit = Object.create(protoRabbit);
+killerRabbit.type = "killer";
+killerRabbit.speak("SKREEEE!");
+```
+
+# Object.prototype
+
+Most objects in JavaScript eventually extend `Object.prototype` through
+parent prototype objects or directly, which provides a bunch of default
+methods[^1].
+
+``` javascript
+console.log(Object.getPrototypeOf({}) == Object.prototype); // true
+console.log(Object.getPrototypeOf(Object.prototype)); // null
+```
+
+# Footnotes
+
+[^1]: <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object>