Having set type, real live lead type, for a large portion of my early years, a pet peeve of mine is referring to a typeface as a font. I realize that they're called 'font files' but that's because whoever generated that name didn't know the difference either. A font is a specific instance of a typeface. Specific size, weight, width, etc. such as 12 point bold extended Garamond. A typeface is a particular style like Helvetica, Futura, Clarendon, etc. That being the case, if there ever was something that should be called a typeface it's what's popularly called a font in digital land.
Then there's this thing that digital text warriors refer to as 'kerning' which is really 'letter spacing'. No matter what you call it, there are rules but the most important rule and the one that digital hacks constantly violate is the notion of 'type body'. A character in a font sits on what's called the face of a rectangular slug of lead. The dimensions to that face, height and width, are the type body. Just picture an uppercase character with a bounding rectangle This is rectangle is inviolate by typesetters, there's no way that any part of any character can occupy any part of the type body of any neighboring character. It's a physical impossibility and is considered bad typography. There are exceptions but those are created by the type foundry, not the typesetter. I've .some fonts with some really goofy-looking slugs in order to accommodate this sort of thing. Digitally, where type body violation can be done out of hand, it's one of those things that you can do but you shouldn't. Ever. Spare me the cries of this being a brave new world where such things can now be done, etc. It's still bad typography. Resist the temptation to slide the left leg of that A under the top portion of the P to its left. Not only does it not look right but it's also bad typography. People have been seeing and reading text created with movable type for almost 600 years and even if they don't know the rules, they know what they're seeing. Violate the rules without having a good reason for doing so and your text will look strange to most people without them actually knowing why.
Thus endeth the lesson.