In Computer Science, a "Bug" is just an error that needs a solution!
The "Grammar" errors. This happens when you break the rules of the programming language (e.g., forgetting a colon or a bracket).
The "Brain" errors. The program runs perfectly, but the result is wrong because your formula or logic is incorrect.
The "Crash" errors. Everything looks fine until the program is actually running and encounters a task it physically cannot do.