Basic research is used to explore the fundamental bases of behavior, without regard to how those bases are manifested in the real world. Basic research aims to explain, predict, and describe fundamental bases of behavior.
For example, a popular memory procedure is to have people respond to words on a computer screen as fast as possible (e.g., saying the word, pressing a key).
This can tell researchers about how information in your memory is linked to other information. Does this ever happen in real life? Outside of a really weird video game, probably not.
Is it important? Yes, it can tell us a great deal about the processes of memory. This procedure is just one example but in fact, much of psychological research is basic research.