What are UNIX© and Unix?

"You need Unix-level performance and reliability. You don't have a Unix-level budget."
Microsoft advertisement (2003)

Kenneth Thompson (left) with
          Dennis Ritchie (right)Unix is one of the oldest OS, originally written (coded) in assembler in 1969 by Dennis Ritchie and Ken Thompson at Bell Labs. Later Unix was written (coded) again in C (its native language) for portability in 1972. Unix is the most portable and reliable OS.

By the way, UNIX© is not the same as Unix. UNIX© (all capital letters and often presented with the copyright symbol) is a trademark while Unix (a proper name) is a philosophy. Considering the latter, BSD and Linux are not UNIX©. They are UNIX© clones, but nonetheless they are considered Unix. If you are confused, you are not alone.

Several vendors have registered versions of UNIX©. They are Tru64 Unix, IBM AIX, UnixWare, IRIX and Sun Solaris.

At the same time, there are several Unix clones like BSD and Linux. For those who work with Windows and do not want to handle a separate OS installation, Cygwin is handy with its Unix-like (Linux-like) environment.

About 90% of the internet relies on a variation of Unix (normally either Linux or BSD), with Apache Software Foundation (ASF). For example, this web site runs on Linux, with Apache, SSI, Perl, PHP, MySQL and Sendmail with FormMail. If you are new to these technologies and would like to try them, go to Apache Friends where you can download everything in one package.

Most (if not all) source code from the various Linux distributions and BSD, Apache, PHP, MySQL and Mozilla are open source. Support the open source community. One way you can do this is by supporting organizations like the Open Source Education Foundation.

Unix Emulators:

Cygwin

Cygwin is an open source "Linux-like environment for Windows [4.x and up]" (emulator) originally developed by Cygnus Solutions and then acquired by Red Hat.

Git for Windows

Git offers a limited open source emulator for Windows in order to access the Git version control system. This emulator is often the choice of open source developers using Windows.

Termux (Android)

Termux is an open source "emulator and Linux environment" for Android with its own package manager (pkg) in a sandbox — little to no chance to destroy or corrupt data.

              pkg install [package_name]