Online advertisements are commercial messages that appear on the internet, usually on websites or social media platforms. They can take different forms, such as banner ads, pop-up ads, video ads, and sponsored social media posts.

Online advertisements can be used by companies to promote their products or services and acquire new customers. They may be targeted to specific demographic groups or users with specific interests, depending on the advertising network or platform used.

There are several ways in which online advertising can be paid, such as by the number of views (impressions), the number of clicks (clicks) or the number of conversions (purchases or other desired actions). Advertisers can also use bidding systems, where they bid on specific keywords or advertising space on a website, and the winner of the bidding process gets the advertising space.

Online advertisements can be an effective way to communicate to a certain audience, but they can also be perceived as disruptive or undesirable by some users. Therefore, it is important to ensure that online advertisements are used responsibly and that they are relevant to the target audience.