What is Typography?
Typography is the do's and dont's of type. From websites to brochures, learning what works and what doesn't when it comes to font is crucial. The more aesthetically pleasing something is the more attention it will draw.
When figuring out how to create the type of your project remember that not everyone has 20/20 vision. Make sure the font is large enough for anyone to read. Losing readers is losing business. Size 16 is safe to use, anything smaller should only be used if necessary.
Choosing a font size should be fairly straight forward. Don't choose anything that you have to squint at, even slightly. There are lists of OK'd fonts online but for the most part just try to keep it simple.
Other aspects to think about are kerning letters, line height, and don't use too many fonts. Text is how people get their information and if you want to get everything across then make it easy to read, keep it simple.