#3576
As an open-source and UNIX-like OS, Linux is so powerful and highly secure that it has been controlling so many IT technology fields of great concern. Therefore, mastering the essential basic knowledge about Linux can make IT professionals scale new heights in work.

#3299
Android-x86 (AKA: Android X86) is an unofficial Android Open Source Project (AOSP) started in 2009 by Chih-Wei Huang from Taiwan. The main purpose of this project is to provide a complete and feasible set of Android system solutions for X86 PC platform, including a whole set of source code tree, supporting documents, as well as Live CD and Live USB.

#3122
Since Red Hat published its last one (9th) release (Red Hat Linux 9) in 2003, they decided not to provide free technical support & product certification any more, and fully turned to the development of Red Hat Enterprise Linux (RHEL for short). This made some Red Hat rebuilders (open-source Enterprise Editions, such as White Box Enterprise Linux, Tao Linux, X/OS Linux, Scientific Linux) were born at the right moment. The most active one is CentOS (short for Community Enterprise Operating System).

#2832
Windows XP SP4 Unofficial, as its name says, it's not a Service Pack released by Microsoft Official site, but it is so popular that XP's loyal supporters call it SP4 of Windows XP after the official final one - SP3.

#1925
Skip the Windows 9, Windows 10 became Microsoft's latest operating system, and its Insider Preview edition has been released for some time (now it has been Insider Preview). Fully named Windows 10 Insider Preview, with OS (Kernel) version NT 6.4 (Windows 8 is 6.2, Windows 8.1 is 6.3).

#1921
Tiny Core Linux (short for TCL) is a lightweight to the minimal, tiny Linux operating system with a GUI. It's constructed based on the 3.x version of Linux kernel with BusyBox, Tiny X, FLTK and other small software, which can be booted from the CD-ROM, USB flash drive or HDD. Additionally, due to all its components running in the RAM, its running speed is super fast.