# JavaScript ES5 教學

## ES5 = ECMAScript 5, 第一個5.x版在2009年12月推出.

JavaScript最新正式版為2015年推出的 ES6, 其中包含了諸多的新功能, 比如說 1. `class` 2. block level的scope變數 `let`, `const`等. 3. 非同步API - Promise <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise> 4. Arrow function 5. 其他

**ES6** 在2015年正式推出, 它包含了 JavaScript ES5的語法, 並推出許多新的語法功能. 現在許多最新版的瀏覽器並沒有實作全部的ES6功能, 通常是 module部份. 而舊版本的當然更不用說了.

故還是會需要從JavaScript ES5 開始學起.

在開始前也可以先參考 [**JavaScript重點整理**](/learning-javascript/javascript-es5-jiao-xue/javascript-zhong-dian-zheng-li.md)

若有物件導向基礎的, 且想先事先知道JavaScript裡面的物件導向是怎麼一回事, 可跳到 [**進階-再講prototype**](/learning-javascript/javascript-es5-jiao-xue/jin-jie-zai-jiang-prototype.md)**一章**


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