Adware is a type of software that automatically displays or downloads advertisements to a user's device. It is often bundled with free applications and can track user behavior to deliver targeted ads. While some adware is harmless, it can slow down devices and disrupt user experience. In some cases, adware may collect personal information without consent, raising privacy concerns. Users can remove adware by uninstalling the associated programs or using specialized removal tools. Keeping software updated and being cautious with downloads can help prevent adware infections.