A computer bug is like a mistake or glitch in a computer program that causes it to act in ways it's not supposed to. It's kind of like a typo in a document that might cause confusion or misunderstanding. The bug might make the program crash, freeze, or produce incorrect results, and it can happen for a variety of reasons. Sometimes it's because the program was written with errors, or there might be a problem with the computer's hardware or software. To fix the bug, programmers need to identify and correct the problem, which can take some time and effort.