ASUS probably has one of the easiest naming schemes of all board manufacturers.
P4(x)533-(x).
P4 indicates that this board is designed for the Pentium 4.
The next letter indicates chipset. P4B, P4T, P4S: B for Brookdale (i845), T for Tehama (i850), S for SiS.
The next set of letters/numbers indicates either year, or featureset.
eg, P2L97 (Pentium II, LX chipset, 1997); P3C2000 (Pentium III, Camino i820, Year 2000), A7V333 (Athlon, VIA chipset, 333MHz RAM support), P4S8X (Pentium 4, SiS chipset, AGP8X).
The suffixes determine the features within a family of boards. A board without the suffix is the base family member.
-E is Extended (big brother version with larger featureset, usually AGP Pro and RAID)
-V is onboard video
-B is AT form factor
-M is MicroATX
-C is Cut down (reduced featureset, ie regular AGP4X, reduced DIMM slots, no onboard sound).
-FX is FlexATX
-L is board LAN (no longer used)
-S is onboard SCSI (rare now, only used for server boards)
-D is for Dual Processors
-F has had several meanings over the years. P2B-F indicated Five PCI slots; P4T-F indicated Four PCB layer board.
Combinations of the above exist as well, most common being -VM (microATX with onboard video), -VF (FlexATX with onboard video), -DLS (dual CPU, onboard LAN, onboard SCSI, generally only for server boards).