SSE : Streaming SIMD Extensions

Technology from Intel.

SIMD lets one microinstruction operate at the same time on multiple data items. This is especially productive for applications in which visual images or audio files are processed. What usually requires a repeated succession of instructions (a loop) can now be performed in one instruction. Intel offers the analogy of a drill sergeant issuing the order "About face" to an entire platoon rather than to each soldier, one at a time.

SSE capable CPU

Intel :

Pentium III
Celeron 533A and above (with Coppermine core, a.k.a. Celeron II)
Pentium 4

AMD :

New Duron (with Morgan core)
Athlon XP (with Palomino core)