Spyware is a software which is installed on your computer to spy on your activities and report this data to people willing to pay for it. It tracks the user's behavior and reports information back to a central source. These are used to spy on some one either for legal or illegal purpose.
Spyware mostly get installed on your PC without your consent. Typically, spyware finds its way onto PCs by piggybacking" onto a file, or gets downloaded from the Internet when you visit a particular website. Pests such as spyware can often lurk silently on your computer until someone or something sets them off, or until they are found and properly removed.
DAMAGE CAUSED BY SPYWARE
Spyware can act like a peeping tom or, at worse, a geeky thief. For example, it :
》Compromises your data, computing habits, and identity. Spyware can monitor information about your computing habits, such as what websites you visit, or record your keystrokes, which in the end can lead to identity theft. For example, spyware can record the keystrokes that you use while keying in a credit card number and send this number to a "cyberthief."
》Alters PC settings. Some forms of spyware can also alter computer settings like your web browser home page setting or the placement of your desktop icons. This doesn't do much damage to your PC, but it's really annoying.
》Slows down your PC. Spyware can rob your PC or system speed and Internet access efficiency. This can become a big problem when you're trying to use the programs on your PC, watch videos online, or download large files.