By all means learn typography, but always remember that not everyone is going to experience your site the same way. People with less than perfect vision(there's

By all means learn typography, but always remember that not everyone is going to experience your site the same way. People with less than perfect vision(there's more of them than you might think!) will often change their browser defaults to enlarge the text. Some people use screen readers. And a few people will alter your design with their own custom CSS.