Typesetting and layout are about readability and what sort of reading experience you are giving the reader.

Knowing why different letterforms read differently (serif vs. sans-serif, bold vs. normal, etc.) is essential for readability. The amount of space between lines is important -- indeed, the default is rarely the best option. The kerning, as you say.

Knowing how many characters you can put in a line and still maintain easy reading. Knowing what justification and non-justification do to the reading experience. These things are all typesetting.

Check out this website. IT also has a good companion book.