Definition of Malware - Malware is a generic term for any type of "malicious" program, using all sorts of tricky methods to get itself onto your computer. It will often pretend to be something else, like a piece of software you want, hidden in a file you've been sent or even appearing to be a warning from a
virus checker.
Once it's on
your computer and embedded into the memory, it can do anything from trying to capture your passwords and bank details, deleting important files or even allowing someone else to enter and take over your system.