Sometimes they arrive as
Sometimes they arrive as an automatic download from a website you are surfing. Porn and online gambling sites are notorious for this, for example.
Sometimes, if you download a free or illegal piece of software, they are embedded in the installation process, or spyware can get on your computer via an email attachment that you shouldn’t have opened. (Tip here – if an e-mail comes from an unrecognized source with an attachment, DO NOT open it – it’s almost guaranteed to be some sort of program that you definitely don’t want!)
Spyware and adware are bad news for several reasons:
They hog precious system resources like memory and hard disk space. If you computer runs much slower than it did previously, then it probably is infected with spyware. If you have never done a spyware scan, then it?s almost guaranteed that there is spyware on your system slowing things down.
They can seriously compromise your privacy and security, providing outsiders with information about your computer habits.
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