We explain what Unix is, the history of its creation and the various uses it has. In addition, we explain its characteristics, advantages and disadvantages.
What is Unix?
Unix is known as the brand of a family of computer operating systems developed from the 1960s onwards and characterized by being open source, meaning that their own users can contribute to their development, updating and improvement, as well as being portable, multitasking and multi-user.
There is, therefore, no single version of Unix, but rather a series of commercial applications and developments called “implementations”some of which are sold on the market with copyright and others offered free of charge among user communities and computer groups.
Even so, there is talk of “traditional Unix” to refer to the more or less standard version. The rest can be referred to as “Unix-like”.
What is special about Unix is its utility for jointly managing resources of a machine between various users, assigning them to each one based on a shared time.
It is also the operating system most used by hackers in the world.
See also: Windows 10.
Unix history
The first Unix developers were Dennis Ritchie, Ken Thompson, Douglas McIroy and Joe Osanaprogrammers at AT&T’s Bell Laboratories, a company that sold the rights to the system to Novell Inc., who resold them to Santa Cruz Operation (1995) and this in turn to Caldera Software (2001), later the SCO group.
However, Novell always warned that it sold the rights of use and not ownershipso after a long legal conflict, he recovered the copyright in 2010.
UNIX® registered trademark
The name “Unix” It was initially UNICSacronym for Uniplexed Information and Computing System, a name that supposed a version (hack) of Multics systems.
The name was later changed to Unix and is registered as a trademark and copyrights all Unix systems that comply with the “Single Unix Specification”, a series of identification standards for the systems of said family.
However, the term became popular as the equivalent of the entire familywhich is why numerous free variants distributed on the Internet choose to be called UN*X, UNIX*, *NIX or *N?X.
General Unix Features
In general terms, UNIX It is a multi-user operating systemwritten in the C programming language, with the ability to simulate multiprocessing and non-interactive processing.
It also has process interconnection capacity, which allows communication and demonstrates great ease in redirecting inputs and outputs. All this makes it an environment with facilities for creating programs and systems, as well as software designs. Hence its enormous popularity.
Unix uses
Unix is often used in the control of multiple user systems and peripherals, in complex resource management systems and, also, by advanced users such as programmers or software designers. Above all, it is used in internal or corporate networks and in joint computing systems.
Unix Advantages
Unix has proven to be a powerful operating system, a very high adaptabilitywhich also allows the connection of multiple users to a central brain.
Its high compatibility and programmability make it ideal for the management of various peripherals (printers, scanners, cameras, etc.), as well as for creating pieces of software. Hence, it is the most popular operating system among hackers and independent programmers.
Disadvantages of Unix
Unix has notable disadvantages and risks, such as those implied by their lack of technical support: poor computer security and high standards of demand from the user, who must generally be very experienced.
Likewise, being open source, much of the computing material available for Unix is developed in-house, without any quality control.
Unix portability
Unix is distinguished from other operating systems such as MS-DOS in that There is no physical disk (a partition, an external disk, etc.), since everything in it is a file and is “transparent”.
The user interface is precisely a hierarchical tree of files. This, added to the representation of the peripherals also as files, entails their enormous portability, one of their most important functions.
Unix Elements
Unix systems are based on two fundamental components:
- SHELL. A programmable control language that establishes communication with the operating system, which simultaneously operates as an interpreter, messenger and programmer. It can be used to dynamically modify the characteristics with which programs are executed.
- KERNEL. A kernel permanently residing in memory, which operates as the heart of the system: it handles system calls, manages file access, and starts or suspends user tasks (resource allocator).
Basic Unix Commands
The basic user commands in Unix can be summarized (at least the main ones developed in the first edition) as follows:
- Browsing and creating directories and/or files: ls cd pwd mkdir rm rmdir cp.
- Editing and viewing files: touch more ed vi nano.
- Text processing: echo cat grep sort uniq sed awk tail head.
- File comparison: comm cmp diff patch.
- System administration: chmod chown ps find xargs sd w who.
- Communications: mail telnet ssh ftp finger rlogin.
- Shell: sh csh ksh.
- Documentation: man.
Best-known Unix families
The main Unix families that are known are:
- AT&T. The “pure” or “original” Unix family, whose most important versions are UNIX System III and UNIX System IV.
- BSD. As a result of Unix licensing to the University of Berkeley, it was completely rewritten to lack any copyright elements from the original software.
- AIX. Also arising from a licensing and rewriting of the code, this time to IBM.
- GNU. An attempt to create a freely distributed variant of Unix, called the “GNU Project”, in 1983.
- Linux. Created in 1991 by Linus Torvalds, who combined GNU tools with his own kernel and created a kind of Unix “clone” that does not come from its original history.