JavaScript is a popular programming language used for building dynamic and interactive web applications, while jQuery is a JavaScript library that simplifies the process of manipulating HTML documents and handling events. While JavaScript offers a wider range of features for complex web applications, jQuery provides a streamlined approach to common tasks, such as animating elements, handling form submissions, and making AJAX requests. Choosing between JavaScript and jQuery depends on the project's complexity, development expertise, and preference for either a low-level or high-level approach to web development.