JavaScript is one of the 3 languages all web developers must learn: 1. HTML to define the content of web pages. 2. CSS to specify the layout of web pages. 3. JavaScript to program the …

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A JavaScript function is a block of code designed to perform a particular task. A JavaScript function is executed when "something" invokes it (calls it).

What is JavaScript? JavaScript is the programming language of the web. It can update and change both HTML and CSS. It can calculate, manipulate and validate data.

JavaScript comments can be used to explain JavaScript code, and to make it more readable. JavaScript comments can also be used to prevent execution, when testing alternative code.

Common uses for JavaScript are image manipulation, form validation, and dynamic changes of content. To select an HTML element, JavaScript most often uses the …

JavaScript Statements. JavaScript statements are composed of: Values, Operators, Expressions, Keywords, and Comments. This statement tells the browser to write "Hello Dolly." inside an …

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JavaScript Form Validation. HTML form validation can be done by JavaScript. If a form field (fname) is empty, this function alerts a message, and returns false, to prevent the form from …

The try statement defines a code block to run (to try). The catch statement defines a code block to handle any error. The finally statement defines a code block to run regardless of the result. …