Red Hat Enterprise Linux (RHEL) is a Linux-based operating system from Red Hat designed for businesses. RHEL can work on desktops, on servers, in hypervisors or in the cloud. Red Hat and its community-supported counterpart, Fedora, are among the most widely used Linux distributions in the world.
Red Hat Enterprise Linux has multiple variants, with server versions for x86, x86-64, PowerPC, Itanium and IBM System z. It also includes desktop versions for x86 and x86-64. As of June 2014, the latest variant of Red Hat Enterprise Linux Version 7(RHEL V7).
Being a Linux distribution, Red Hat Enterprise Linux contains the Linux kernel as well as some applications for performing certain tasks. Like all Linux distributions, RHEL is open source. Thus, people can view its source code, download it and make their own customized versions.
In the past, Red Hat gave this enterprise product for free and only charged for support. Later on, they decided to create two versions: RHEL, which would have less frequent version releases and consequently be more stable, and Fedora, which would undergo relatively more frequent version releases and consequently offer more bleeding edge technologies. Fedora, which is given entirely for free, is sponsored by Red Hat (the company) but is actively developed by a community of developers. It is most suitable for Linux enthusiasts. RHEL, on the other hand, takes technologies developed via the Fedora Project and packages them into a more reliable and stable commercial product. Hence, RHEL is best suited for the enterprise.
A typical RHEL distribution would include development tools, applications, services and utilities such as Compiz, CUPS, DHCP, Firefox, GIMP, MySQL, OpenOffice.org, Samba and Python, to name a few.