Font (or text) decoration: this includes over-lining, underlining, and strikethrough text.

Font effect: modifications made to text such as bevels, inlines, outlines, shadows, which are usually used to make the text more prominent.

Font style: a specific variant of the typeface's appearance which includes case (uppercase, lowercase), skew (roman, italics), etc.

Font weights: the thickness of the lines in each letter. This can range from ultrathin to ultra-black.

Font width: the width of each letter. This is the widest point of the outermost lines of that letter, irrespective of the thickness of each letter.

Letter spacing (aka tracking): space between the widest points of each character. This is often applied to an entire word, sentence, or paragraph.

Kerning: this is the negative space i.e. the "breathing room" between consecutive letters which is often applied to a group of letters.