8.1 introduction
Online advertising is a term often used to describe almost everything covered in this textbook. Simply put, online advertising is advertising on the Internet. Online advertising encompasses adverts on search engine results pages (covered in the chapter Pay Per Click Advertising), adverts placed in emails and on social networks, and other ways in which advertisers use the Internet. However, this chapter focuses on display advertising: graphical and interactive online adverts that are displayed on web pages.