Web browsers are software applications that allow you to view content that is on the internet; whether it be a web page, a video, an image, a document or any other piece of content. There are many different web browsers to choose from including the top ones: Google Chrome, Microsoft Internet Explorer, Apple Safari and Mozilla Firefox.
Both Mozilla Firefox and Microsoft Internet Explorer are popular web browsers. Each have different features (although there are also many similarities) and therefore it is a preference of choice as to whether you use one over the other.