Project types are templates for different kinds of projects. Project types define many aspects of a project and it's behaviour. It can be very convenient to create a separate project type for projects that clearly have their specificities. That way creating a new project with those same specificities is just a metter of selecting the same project type.
List of project types in the system can be accessed by click on setup button 1, then Project Settings section 2 in setup menu followed by click on Project Types button 3.
Like and share