Contextual advertising is a form of online advertising that targets users based on the content they are currently viewing. By analyzing the keywords and themes of a webpage, advertisers can display relevant ads that match the interests of the user. This approach aims to enhance user experience by showing ads that are more likely to resonate with the viewer. For example, if a user is reading an article about healthy recipes, they might see ads for kitchen appliances or organic ingredients. This method increases the chances of engagement, as the ads are tailored to the user's immediate context and preferences.