A computer problem is an issue that affects the performance of a computer system. Common computer problems include worms, viruses, crashes, and bugs. A WORM is a type of malicious software that replicates itself and spreads across networks. A VIRUS is a type of malicious software that can infect a computer system and cause damage to files and programs. A CRASH is when a computer system suddenly stops working or shuts down unexpectedly. A BUG is an error in a computer program that causes it to malfunction.