The term spyware is a neologism made up of spy and software. It is malicious software that is installed on users' computers without their knowledge or consent. Spyware can refer to user behavior, or to spying on sensitive data or user authentication.
As far as user behavior is concerned, spyware can, among other things, spy on and document the surfing ofInternet users. From this behavior, conclusions can be drawn about online marketing and advertising. On the other hand, browser hijackers can change web browser settings in such a way that websitevisitors are redirected to other websites.
Spyware can be installed as unwanted malware to spy on business partner communications and sensitive data such as usernames, credentials, authorizations, passwords, personal identification numbers, account details, email addresses. The spying can be done by banking Trojans, which intercept payment data, access data and steal transfers from the bank accounts of the affected persons. Keyloggers that work with keystroke recognition are also used for this purpose.
Spyware is downloaded to user PCs, desktops, laptops or smartphones through Trojans and with emails. For smartphones, snoopware is used as spyware. It is difficult for users to detect if the computer is infected with spyware. An indication of this can be seen in the reduction of transfer rate and computing speed.