JavaScript
JavaScript Basics
Overview
- JavaScript is one of the most widely used programming languages.
- Primarily used for:
- Web development (front end)
- Mobile development
- Some back end development (e.g., Node.js)
Role in Web Development
- HTML & CSS define layout and style.
- JavaScript controls functionality and interactivity.
- Without JavaScript, web pages would be largely static.
Example Usage
Inline JavaScript
<script type="text/javascript">
// JavaScript code here
</script>
- Within the page source code,
JavaScriptcode is loaded with the<script>.
External JavaScript File
<script src="./script.js"></script>
- A web page can also load remote
JavaScriptcode withsrcand the script's link.
Basic JavaScript Code Example
document.getElementById("button1").innerHTML = "Changed Text!";
- Changes the content of the element with
id="button1". - An example of basic use of
JavaScriptwithin a web page.
Tools for Practice
- JSFiddle for experimenting with JavaScript, HTML, and CSS.
Common Uses
- Real-time updates to page views and content.
- Accepting and processing user input.
- Performing HTTP requests via Ajax.
- Automation of complex processes.
- Driving advanced animations when combined with CSS.
Browser Support
- All modern browsers come with built-in JavaScript engines to execute code client-side.
- Enables fast, interactive experiences without round trips to the server.
JavaScript Frameworks
To enhance development efficiency, several frameworks and libraries are widely used:
A listing and comparison of common JavaScript frameworks can be found here.
These frameworks:
- Provide tools and libraries to build feature-rich web applications.
- Allow dynamic generation of HTML.
- Can be used to simplify common functionalities like authentication.