I can only recognize the most common ones: Arial, Helvetica, Times New Roman, Calibri, Ubuntu, Comic Sans, Roboto, Computer Modern. But more than noticing the

I can only recognize the most common ones: Arial, Helvetica, Times New Roman, Calibri, Ubuntu, Comic Sans, Roboto, Computer Modern. But more than noticing the differences between them, what's important is noticing when there's something wrong in a composition because of the font. For example, if you show a UI that uses a serif font to someone, they'll notice there's something wrong with it, but most people probably won't tell you exactly what it is.