Intel Pentium

Pentium is a brand used for a series of x86 architecture-compatible microprocessors produced by Intel since 1993. In their form as of November 2011^[update], 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, i7, and high-end Xeon series.

As of 2017^[update], Pentium processors have little more than their name in common with earlier Pentiums, and are based on both the architecture used in Atom and that of Intel Core processors. In the case of Atom arcitectures, Pentiums are the highest performance implementations of the architecture. With Core architectures, Pentiums are distinguished from the faster, higher-end i-series processors by lower clock rates and disabling some features, such as hyper-threading, virtualization and sometimes L3 cache.

The name Pentium is originally derived from the Greek word penta-πεντα, meaning "five" (a reference to the prior 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 prior generations (286, i386, i486). However, as the firm wanted to prevent their competitors from branding their processors with similar names (as AMD had done with their Am486), Intel filed a trademark application on the name in the United States, but was denied because a series of numbers was considered to lack trademark distinctiveness.

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