Spyware is considered a malicious program and is similar to a Trojan Horse in that users unwittingly install the product when they install something else. ... Spyware works like adware but is usually a separate program that is installed unknowingly when you install another freeware type program or application.
Unlike spyware, adware does not perform malicious acts.Windows Defender helps protect you from spyware, but it's crucial that you also have antivirus software to help protect you against viruses.
