to be clicked, thus generating revenue for the owner of the website (and the server of the advertisement). Contextual advertising has attracted some controversy through the use of techniques such as third-party hyperlinking, where a third-party installs software onto a user's computer that interacts with the web browser. Keywords on a webpage are displayed as hyperlinks that lead to advertisers. With advertisers and marketers focusing on Brand Safety and Suitability, contextual advertising plays a role in protecting a brand's value. Brand positioning and contextual advertising are directly correlated to user perceptions so it is important for marketers to protect their brands by using appropriate contexts. Agency roles There are several advertising agencies that help brands understand how contextual advertising options affect their advertising plans. There are three main components to online advertising: creation—what the advertisement looks like media planning—where the advertisements are to be run; also known as "placements" media buying—how the advertisements are paid for Contextual advertising replaces the media planning component. Instead of humans choosing placement options, that function is replaced with computers facilitating the placement across thousands of websites. Notes Further references Advertising Online advertising methods