An index page serves as a gateway to information on a website, similar to a table of contents in a book. There are several synonyms for the term index page, including homepage, landing page, start page, and portal page. The homepage is typically the first page a user will see when they visit a website, while the landing page is designed specifically to encourage visitors to take a particular action, such as filling out a form or making a purchase. The term start page is often used in the context of web browsers, referring to the page that loads upon opening the browser. Finally, a portal page is a comprehensive index page that provides access to multiple websites and resources.