And then the machine code runs, pretty fast.

Then it converts (“compiles”) the script to machine code.

The engine (embedded if it’s a browser) reads (“parses”) the script.

For instance, if “a feature X is supported by V8”, then it probably works in Chrome, Opera and Edge.Įngines are complicated. The terms above are good to remember because they are used in developer articles on the internet.

…There are other codenames like “Chakra” for IE, “JavaScriptCore”, “Nitro” and “SquirrelFish” for Safari, etc.

The browser has an embedded engine sometimes called a “JavaScript virtual machine”.ĭifferent engines have different “codenames”. Today, JavaScript can execute not only in the browser, but also on the server, or actually on any device that has a special program called the JavaScript engine. But Java was very popular at that time, so it was decided that positioning a new language as a “younger brother” of Java would help.īut as it evolved, JavaScript became a fully independent language with its own specification called ECMAScript, and now it has no relation to Java at all. When JavaScript was created, it initially had another name: “LiveScript”.

Java script writer