A Rendering Engine is a software component that converts web content, such as HTML and CSS, into visual representations on a screen. It processes the code and generates the layout, styles, and images, allowing users to view and interact with websites. Popular rendering engines include WebKit, Blink, and Gecko. Rendering engines play a crucial role in web browsers like Google Chrome and Mozilla Firefox. They ensure that web pages are displayed consistently across different devices and platforms. By interpreting the code, rendering engines help create a seamless user experience, making the web accessible and visually appealing.