No. Hybrid implies that there is a mix with something else. Fedora uses only the Linux kernel.
RT Linux is a specific distribution of Linux, as is Fedora. You can install RT Linux over Fedora, but RT Linux isn't a program you install in a Fedora installation, but an entirely different installation altogether (and meant for different things; RT Linux is meant for specialty devices where the machine needs to manage devices and calculations in Real-time whereas Fedora is more a desktop/server distribution.)
Fedora Core and later Fedora !
Fedora and openSUSE are the open-community spin-offs of privately managed and developed for-profit GNU/Linux distributions, Red Hat Enterprise Linux and SUSE Enterprise Edition Linux.
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GNU/Linux? Plenty. Debian, Ubuntu, Arch Linux, Gentoo, Slackware, Fedora, and many more. Non-GNU Linux? Android.
Red Hat Linux was discontinued in 2004 in favour of Red Hat Enterprise Linux for enterprise environments. However, Red Hat Linux still exists as "Fedora", free for home use, developed by "Fedora Projects", though the entire line is no longer commercial and only supported by the Linux community.
Anaconda is an installer used by Red Hat and Fedora.
Fedora is a desktop-oriented Linux distribution, and ususally features Red Hat's more experimental software.
The term "main difference" is vague and subject to interpretation. I'll try to list a couple of what some folks consider "notable" differences. 1) Redhat Linux is normally purchased and various levels of support are also available for purchase. Fedora Linux is free (free as in beer as the saying goes). 2) Redhat Linux contains some features/enhancements not necessarily found in Fedora Linux or CentOS Linux - mostly these features are designed for enterprise environments. Hope this helps.
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Most desktop Linux distributions (Ubuntu, Fedora, PCLinuxOS, OpenSUSE) are equally suitable for laptops.