Introduction to JavaScript Fundamentals

What is JavaScript?

• JavaScript is like the CPU or brain of a website, changing HTML and CSS in real-time.
• It's the most popular and widely used language for scripting on the internet, recognized by all major browsers.

Features of JavaScript

• Creates and sets the behavior of website contents, such as movements, page refresh, or changes in the screen without manual refreshing.
• Features include animated graphics, photo slideshows, autocomplete text suggestions, and interactive forms.

History of JavaScript

• Developed by Brendan Eich of Netscape, originally named Mocha, then renamed LiveScript, and finally JavaScript.
• Influenced by the C language, but users without a programming background often prefer JavaScript due to its ease of use.

Characteristics of JavaScript

• Case-sensitive language, with quotation marks playing a crucial role.
• Incomplete or missing quotation marks can cause the browser to load and display incorrectly.
• Semi-colons at the end of each statement are not required but are recommended for readability and standardization.

Relationship with HTML and CSS

• HTML refers to the structure of the web page, including headers, body text, and images.
• CSS controls the appearance of the web page, including customized fonts, backgrounds, and colors.
• JavaScript adds interactivity and functionality to websites, making them more dynamic.

Uses of JavaScript

• React to events or interactivity to websites, such as mouse clicks and preloading of web pages.
• Validate data, saving processing time for forms that require user input.
• Create cookies to save or retrieve information from a visitor's computer.
• Enhance a web page, adding items such as pop-up window boxes, animations, or dynamic images.
• Develop mobile applications used in smartphones and tablets.
• Create web browser-based games played directly from web browsers.
• Power back-end web development, including codes needed to build databases, servers, and applications.

Advantages of Using JavaScript

• Supports structured programming syntax, including if statements and while loops.
• Offers dynamic typing, allowing the type of a variable to change even during runtime.
• Runs locally in a website, enhancing interaction and responsiveness.
• Responds to user actions, such as mouse clicks.

Disadvantages of Using JavaScript

• Not supported by some browsers, such as PDA's and mobile phones.
• Some browsers disable JavaScript execution as a security feature.