JavaScript is the most prominent scripting language used to create interactive web pages. You can make highly functional web sites. HTML lets you create static pages and JavaScript helps in making dynamic pages. In this JavaScript Tutorial you will learn the basics of scripting and how to make interactive pages.

Features of JavaScript
Before learning basics in JavaScript Tutorial, let’s understand the features of this scripting language.
- It is a scripting language that can only be used to add scripts in HTML pages. It cannot be used to make stand alone applications.
- JavaScript helps in efficient client-side programming.
- It is interpreted language. Browser reads the script commands in the sequence they are written.
- JavaScript uses Object Oriented paradigm. It identifies each element of a web page. These HTML page elements can be manipulated with methods using the properties of these elements. The top hierarchy elements are window and document. All the HTML elements like table, image, textbox, dropdown etc.
- JavaScript has a whole range of operators, functions, control statements, objects to make interactive pages.
- JavaScript is case sensitive scripting language. Date and date are different in JavaScript.
Use of JavaScript script in a HTML page
- Add client-side functionality in a web page.
- Respond to button clicks.
- Manipulate text of a page.
- Perform data validation checks for data entered by users in HTML forms . This is done before it is sent to server.
- Manipulate images based on user actions.
- Displaying alert message to users with pop-up windows.
- Creating of dropdown menus and perform action on the basis of user selection.
- Evaluating data entered by users and display results
- Assessing user device and manipulation of page on the basis of screen resolution.
- Animating web pages.
- Adding multimedia elements in the web pages. These elements can be hidden, shown, changed or resized.
Adding JavaScript in a Webpage
A JavaScript script can be added in an HTML web page between <SCRIPT> </SCRIPT> tags. JavaScript scripts are added anywhere in a webpage. The language attribute must be given the value ”JavaScript” (case sensitive) to add JS scripts for interactivity.
<SCRIPT LANGUAGE="JavaScript"> JavaScript code </SCRIPT>