Type, and the ability to manipulate type, can elevate a good designer to a great one. It’s a fundamental skill that requires years of study, and is never mastered. If you’re a new designer, this is a great resource to keep handy. It will help you identify the differences and personalities of type faces, allowing you to better choose a face that compliments your design.
If you’re a client of an agency, this is a good resource for you, too! A basic understanding of type faces will allow you to better communicate with your design team.