Rendering Engines
A web rendering engine or a web browser engine is a computer program that loads all resources from a web page and converts them into an “interactive image” (that is, you not only see the visual representation of the page, but you can also navigate to another pages or submit forms). This process is known as “rendering” and it follows a certain specification in order to get the same result, even if the different engines handle differently HTML, CSS, JavaScript, images, and other web resources.
Except for the text web browser, all web browsers use a rendering engine. Basically this is exactly what determines the speed and correctness of rendering web pages. See the list below to find out which browsers use a particular engine.