Most Malware focus on gaining entry over the internet to a secure computer system by finding a working user ID and password combination.
Step-by-step explanation:
A malware is a small computer program which works on the user’s system without knowing to the user. Different malware works differently.
Some malware sits on the user computer, create multiple unnecessary files and make the hard drive full, some people create viruses to show their computer skills which they tend to prove in a wrong way, some malware sits in the computer to steal data especially while using internet.
So there are malware's like Virus, Worm, Trojan, spyware, etc.