Chapter 4. JavaScript API

JavaScript is the scripting language used in web browsers for client-side programming tasks. As used in browsers, it is a dialect of the standardized ECMAScript[93] programming language. JavaScript programs can execute all kinds of simple to complex tasks for web pages, ranging from the manipulation of a simple user interface feature to the execution of a complex image analysis program. JavaScript overcomes the limitations of HTML and CSS by providing full flexibility to change anything in the Document Object Model (DOM) programmatically.

Because JavaScript support can be turned off in a web browser, it was important to explain what HTML and CSS provide without further scripting. Adding JavaScript to the mix, however, ...

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