"Client-side" refers to operations that are performed on the user's device, such as a computer or smartphone, rather than on a remote server. This includes tasks like rendering web pages, processing user inputs, and executing scripts. Technologies like HTML, CSS, and JavaScript are commonly used to create interactive and dynamic content that enhances the user experience. In web development, client-side programming allows for faster response times since actions do not require communication with a server. This can lead to smoother interactions, such as animations and form validations, making applications more user-friendly. However, it also means that the performance can vary based on the user's device capabilities.