This keeps coming up. Here are what the different things are:
Torx: 6 pointed
Tamper-proof Torx: 6 pointed with a round peg in the middle
Torx Plus: 6 pointed, but the points are rounded off
Tamper Proof Torx Plus: 5 pointed, points rounded off, peg in the middle (yes, they are FIVE pointed).
XZN (Triplesquare): 12 points
Allen: 6 sided hollow hex
Polydrive: 6 widely spaced rounded points (used on some head bolts).
There is no such thing (technically) as "Star".
Read all about them here:
http://en.wikipedia.org/wiki/Torx