Different programming languages are used for various purposes, with Java, PHP, and JavaScript being some of the most popular and widely used languages. Java can be used for mobile, enterprise, and desktop applications as well as Android apps. PHP is useful for quickly building web apps and is the foundation of content management systems like WordPress. JavaScript allows developers to add interactivity and animations to web pages. Some other common languages mentioned are Python, Objective-C, Ruby, Perl, C/C++/C#, SQL, and Swift. Each language has its own strengths and uses.