Search advertising is the promotion of ads on search engine listings or on the sidebar of search engine results pages (also known as SERPs). Search advertising is a very popular channel, largely due to the sheer volume of traffic seen by SERPs. It was estimated that there were 1.2 trillion searches on Google in 2017. When a person uses a search engine, they are actively looking for something – whether it be a product to buy, a service, or information. Search ads are regarded as extremely effective as they reach users when they are actively engaged with a search query, which means they are more likely to click and convert. Search ads are available on all search engines, such as Google. Bing, Yahoo and others.