Topic
JavaScript
JavaScript is a programming language used in browsers and other execution environments.
At a glance
- Language standard
- ECMAScript
- Browser interaction
- Environment APIs such as the DOM
Overview
JavaScript is a programming language used in browsers and other execution environments. It provides expressions, functions, objects, and control flow; the environment supplies additional capabilities such as browser document access or server-side filesystem operations.
Language and environment
The language defines how values and programs behave. Browser and server runtimes add their own APIs, so sharing JavaScript syntax does not guarantee that code can use the same external capabilities everywhere.
Asynchronous work
Promises and related language features help express work whose result arrives later. Applications must handle successful completion and failures, especially when a request or external operation can finish after the interface has changed.
Sources and review
MOOR's explanatory text is supported by the following source links.
- JavaScript introduction — MDN Web Docs
- Introduction to Node.js — Node.js