What are media queries used for in CSS?

Media queries in CSS are primarily used to apply styles based on device characteristics, such as screen size, resolution, and orientation. By utilizing media queries, web developers can create responsive designs that adapt to different device environments. This allows for a more tailored user experience, where styles can change depending on the user's device, ensuring that content is displayed optimally across various platforms.

For example, a media query might specify that certain styles should only be applied if the screen width is less than 600 pixels, which is common for mobile devices. This targeted approach helps maintain usability and aesthetics, enhancing the overall functionality of a website across different devices.

While applying styles based on user preferences, defining color schemes for dark mode, and compressing image sizes dynamically are important aspects of web development and design, they do not encompass the primary purpose of media queries. Media queries specifically focus on adapting CSS styles according to the characteristics of the device being used to view a webpage.