Final answer:
Red Hat Enterprise Linux (RHEL) is the commercial Linux distribution by Red Hat designed for enterprises. Linux became a popular OS because of its affordability and versatility, leading to widespread adoption in servers and PCs, and its ability to power supercomputers.
Step-by-step explanation:
Red Hat Enterprise Linux (RHEL) is Red Hat's enterprise-ready, commercially-supported Linux distribution. It leverages the open-source nature of the Linux kernel, originally created by Linus Torvalds in 1991, which gained significant popularity due to its free distribution and configurability. The adaptability of Linux has allowed it to be used in a wide array of applications, from PCs to embedded systems, to powerful clusters used by organizations like NASA. Manufacturers such as IBM and Dell began offering Linux as an alternative to reduce costs and break Microsoft's OS monopoly, contributing to the widespread adoption in servers and as operating systems for various hardware.
Red Hat, among other distributions like Debian and Ubuntu, represents a tailored solution for businesses and is known for its stability and support. The importance and impact of Linux can be felt across many industries, with all systems on the Top-500 supercomputer list now running various distributions of Linux. This revolution led to a decline in market share for proprietary systems and established Linux as a dominant force in the software world.