Both Linux and Unix sound very similar to each other and they are both in fact is similar because they have many things associated with one another.
Both can be used as an operating system that can do well for you but in order to have a better picture on the difference between them, let us take a further look into them.
UNIX is copyrighted name only big companies are allowed to use the UNIX copyright and name, so IBM AIX and Sun Solaris and HP-UX all are UNIX operating systems. The Open Group holds the UNIX trademark in trust for the industry, and manages the UNIX trademark licensing program.
Most Unix systems are commercial in nature.
In the older days, Unix was the only option for corporations. Linux was an operating system that spawned off from Unix. It was initially an academic project and was not even being considered for networking purposes. Things only changed after a few years as the system head mainstream because there a many software developers out there using it and providing support for it. Since then, Linux has emerged to be a solution for small to medium sized operations while Unix remains the choice for more demanding operations where multiple process and systems are involved.
System Administration Tools
1) UNIX comes with its own tools such as SAM on HP-UX.
2) Suse Linux comes with Yast
3) Redhat Linux comes with its own gui tools called redhat-config-*.
However, editing text config file and typing commands are most popular options for sys admin work under UNIX and Linux.
Distribution Cost
As for the cost for the distribution of these two systems, Linux will be ahead of Unix because it remains as an open-sourced option. Users can obtain it for free unless they are planning to use it on a server environment. If that is the case, they might have to make a initial purchase. Unix on the other hand requires a fee making it costlier than Linux. If you include hardware, a Unix server might cost from $25,000 and above. therefore, Unix is in a difficult position to be competitive towards Linux. This makes it even easier for users to choose the latter of the two hosting option.
Security Firewall Software
Linux comes with open source netfilter/iptables based firewall tool to protect your server and desktop from the crackers and hackers. UNIX operating systems comes with its own firewall product (for example Solaris UNIX comes with ipfilter based firewall) or you need to purchase a 3rd party software such as Checkpoint UNIX firewall.
UNIX Operating System Names
A few popular names:
1) HP-UX
2) IBM AIX
3) Sun Solairs
4) Mac OS X
5) IRIX
Linux Distribution (Operating System) Names
A few popular names:
1) Redhat Enterprise Linux
2) Fedora Linux
3) Debian Linux
4) Suse Enterprise Linux
5) Ubuntu Linux
Technical
a) In UNIX 'Development' is targeted toward specific audience and platform. Linux development is diverse. Linux standard base was formed to alleviate this problem but it wasn't of much help.
b) UNIX maintains consistency between different versions. Have a published standard that they follow for their customer. Linux have inconsistencies between versions and no strict standards for tools, environment and functionality.
c) In UNIX developers are bounded by standard while in Linux developers are free and have no restriction.
d) In UNIX commands, tool and utilities etc are rarely changed over versions. Hence it is easy to for administrator to update their skills. Moreover tools and application can be used on new edition of OS without a large body of testing. In Linux commands, tools and utilities may change over time.
Updates and Bugs
Every OS, including UNIX and Linux, suffers from vulnerabilities
and bugs that have to be patched, fixed and updated. But Linux enjoys
a clear
advantage over its elder sibling in this department.
Linux bugs tend to die an early death, because the OS undergoes an incredible
amount of scrutiny in the global open-source community
Common Things Between Linux & UNIX
Both share many common applications such as:
1) GUI, file, and windows managers (KDE, Gnome)
2) Shells (ksh, csh, bash)
3) Various office applications such as OpenOffice.org
4) Development tools (perl, php, python, GNU c/c++ compilers)
5) Posix interface
Growth
The growth of Linux in recent years has been proving it to be a solid solution for users out thee especially when used in a server-based operating system. This has force Unix to customize their features to make it more compatible with Linux in order to stay competitive. Unix systems like AIX, Solaris and HP-UX have all been modified and integrated to make it more similar to Linux. So, you can say that Linux has become more powerful than Unix in today's world of operating system.
