Useful Typeface Terminology (please click to enlarge)
Spine - Curved stroke of a capital "S"
Arm - stroke attached at one end
Bowl - curved stroke which encloses a space
Ascender - stroke which extended above the x height
Stress - thickening of a curved stroke
Stem - straight vertical stroke
Cap height - height of capital letters from baseline
Stroke - basic linear element - can be horizontal, vertical, diagonal or curved
Descender - stroke which extended below the baseline
Eye - small counter of lower case "e"
Terminal - end of a stroke
Spur - small projection off of a stroke
X height - height of lower case letters, excluding any ascenders or descenders (usually measured by lower case "x")
Apex - angular peak of capital "A"
Bar - horizontal stroke attached at both ends
Branch - connecting stroke
Counter - enclosed space within a character
Shoulder - curved stroke at the top of a character
Tail - diagonal stroke below the baseline