Adware is software that serves up advertising banners or pop-ups. Usually this is to the detriment of using the software for its core function. Typically, the business model of the adware developer is to generate money from the company behind the advertisements. The reason adware is detected by Antivirus due to either the ads being served are from untrustworthy online companies, or the ad pop-ups are impossible to stop or close, displaying virus like behaviour.
A by-product of Adware is malvertising, when malware-laden advertisements are injected into legitimate advertising space online for the user seeing the website with adware installed.
How to stay protected against Adware
Using TotalAV Real Time Protection will prevent adware from getting on your computer in the first place. Running regular Anti-virus scans, either manually or through a defined schedule, will ensure any adware on your computer are stopped and removed.