JavaScript is a versatile programming language commonly used for creating interactive and dynamic web content. It runs on the client side, enabling developers to enhance user experiences by adding functionality to websites and web applications. JavaScript is known for its ease of use and wide adoption, making it an essential tool for front-end development. It allows developers to manipulate web page elements, handle user interactions, and perform various tasks such as form validation and data manipulation. JavaScript can also be used on the server side with Node.js, expanding its capabilities to build scalable and real-time applications. With its extensive library ecosystem and constant updates, JavaScript remains a pivotal language for web development and beyond.