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This video will explain the origins of JavaScript, and how it relates to the ECMAScript standard.
If you want to create a complex website, maybe something with interactive maps or 3D graphics, for instance, you need to use JavaScript. But what is JavaScript, and where does it come from? Let's find out. A lot of people struggle to define ECMAScript. They wonder if it's the same as JavaScript, and if it is, why do we need two names for the same thing? Let's dig a bit deeper into this and find out.
Before we talk about JavaScript, we need to talk about Ecma International, which is an organization that creates standards for technologies. They've been operating since 1961, and in that time, they've created a wide range of global technology standards. ECMA-262 is a standard published by Ecma International. It specifies a general-purpose scripting language.
The language is called ECMAScript. The ECMAScript standard defines the rules, details, and guidelines that the scripting language must observe to be considered ECMAScript compliant. So that's ECMAScript. But where does JavaScript come in?
JavaScript is a general-purpose scripting language that conforms to the ECMAScript specification. The ECMAScript specification is a blueprint for creating a scripting language. JavaScript is an implementation of that blueprint. On the whole, JavaScript implements the ECMAScript specification as described in ECMA-262. But there are some key differences.
So how do we run JavaScript? JavaScript can run in browsers such as Chrome and Firefox because they contain a JavaScript engine. The JavaScript engine is a small program that reads and executes JavaScript code. But not all JavaScript engines are the same. The engine in Chrome is called V8, whereas Firefox uses SpiderMonkey.
The different engines can sometimes implement JavaScript differently. For example, one engine may run JavaScript code faster than the other. There are also differences in the way browsers support the language. When a new edition of ECMAScript is released, JavaScript engines tend not to integrate the entire update all at once. They incorporate new ECMAScript features incrementally, which means that browser support for the latest features of ECMAScript is always evolving.
Fortunately, there is a website that allows us to check the compatibility of ECMAScript features across browsers. It's called caniuse.com. So now you understand the difference between ECMAScript and JavaScript. But what about ES6 or ES2015? You may have seen references to these two around the web. ES6 is the sixth edition of the ECMA-262 standards. ECMA renamed ES6 to ES2015. 2015 is the year the standard was released. This means the other annual releases can be named according to the year. ES2016, ES2017, etc.
You could search online to see the latest version of ECMAScript and how browsers support it with their JavaScript engines. And that's it for this video. Let's recap what we've seen in this video. JavaScript is a general-purpose scripting language that conforms to the ECMAScript specification. A JavaScript engine is a program or interpreter that executes JavaScript code in a browser. Different browsers use different JavaScript engines. Last up, ECMA-262 is the name of the standard that represents the scripting language specification ECMAScript.