What is the function of JavaScript libraries like jQuery?

JavaScript libraries like jQuery are designed to streamline the process of working with HTML documents, handling events, and creating animations. jQuery simplifies the syntax needed for common tasks, allowing developers to perform complex operations with fewer lines of code compared to standard JavaScript. For instance, instead of writing verbose code to select elements, manage events, or animate properties, developers can use jQuery's concise methods to achieve the same result more efficiently. This reduces the overall complexity of a project and speeds up the development process, making it a popular choice for web developers looking to enhance user interaction and visual appeal on their websites.

In contrast, other options focus on different aspects of web development. Managing server-side scripting pertains to languages like PHP or Node.js, which handle back-end processes. Providing templates for web applications is more relevant to frameworks or templating engines, and optimizing images involves technical aspects of file compression and format selection, which do not fall under the primary functions of JavaScript libraries.