Realistic art is an style that focuses on making pieces look as realistic and true-to-life as possible. Think of realistic portraits, landscapes, and still life paintings. These are all forms of realism which aim to capture the subject in a realistic style, and possibly to portray the subject in a way that captures the realities of life.
Realistic art is that which is not abstract, it’s also called representational art. Its an art that looks almost photographic.