A bug, also known as a defect or software error, is a problem that happens in a computer program, making it act strangely, give wrong results, or even crash.

These problems can happen because of mistakes in the code, errors in how the program works, or not handling data well. In software development, it’s super important to find and fix bugs so that the program works smoothly and doesn’t cause any problems for users.

To put it simply, a bug is like a hiccup in the system that needs to be sorted out to make the program run properly. Developers spend time tracking down and fixing bugs to create software that works just like it should, giving users a better experience.