After the Pentium I, the fastest Intel processor available was the Pentium II. Introduced in 1997, the speeds for this processor range from 233MHz to over 400MHz. It was designed for Multimedia applications with special on-chip multimedia instructions and high-speed cache memory.
Celeron was a low-end version of the Pentium II. It might be called a Pentium II with less (or no) level 2 cache. Pentium II was designed to be used in PC's. However, Pentium II Xeon was a high-end version that was based on the same Pentium II circuitry with the intention of using it on multiprocessor severs and workstations.
Pentium II was packaged in a slot-based form-factor instead of a socket one, unlike previous makes of Intel processors; thereby allowing Intel to separate the secondary cache from the processor; though still keeping it on a closely coupled bus. The separate cache was comparatively slower (i.e., ran at half the processor speed) than in the Pentium Pro but was not expensive.
