Meeting types are meetings that you schedule often and usually have the same scheduling parameters. These tend to align to your job and your day to day workflow. If you are a recruiter you probably do a lot of screening calls, and if you are an AE you probably do a lot of demos. These meetings should be set up as personalized meeting types, so you don't have to repeatedly tell Amy and Andrew what you want.
A meeting type has its own preset details like timing, meeting title, duration and location. For example you could set up a meeting type called “Demo” that's 30 minutes long, includes your Zoom details, is only scheduled Tuesday through Thursday, and is titled “Company XX Demo.”
You can setup as many meeting types as you like to cover all the events you typically schedule.