Pentium

Pentium is a brand used for a series of x86-compatible microprocessors produced by Intel since 1993. In their current form, Pentium processors are considered entry-level products that Intel rates as "two stars", meaning that they are above the low-end Atom and Celeron series but below the faster Core i3, i5 and i7 lines as well as the high-end Xeon processors.

The current Pentium processors have only the name in common with the early ones, and are in fact based on the Intel Core architecture, typically implemented by lowering the clock frequency and disabling some features, such as hyper-threading, virtualization and, partly, L3 cache.

The name Pentium is originally derived from the Greek word penta-πεντα, meaning "five" (a reference to the previous numeric naming convention of Intel's 80n86 processors (80186-80486), with the Latin ending -ium.

During development Intel generally identifies processors with codenames, such as Prescott, Willamette, Coppermine, Katmai, Klamath or Deschutes. These usually become widely known, even after the processors are given official names on launch.

The original Pentium branded CPUs were expected to be named 586 or i586, to follow the naming convention of previous generations (286, i386, i486). However, as the company wanted to prevent their competitors from branding their processors with similar names (as AMD had done with their Am486), Intel attempted to file a trademark on the name in the United States, only to be denied because a series of numbers was not considered distinct.

...
Wikipedia