The world of colleges and universities is academia. Academia is the academic world.
If you like school, then you might enjoy academia, which is also known as academe. People in academia include students — college and university students, specifically. Then there are the professors, who teach the students. That's not all professors do; they also research various subjects. Producing research is one of the major goals of academia. If you like thinking and learning and studying, academia could be the place for you.