Unix:

Unix is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, development starting in the 1970s at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others.

Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors like the University of California, Berkeley (BSD), Microsoft (Xenix), IBM (AIX), and Sun Microsystems (Solaris). In the early 1990s, AT&T sold its rights in Unix to Novell, which then sold its Unix business to the Santa Cruz Operation (SCO) in 1995. The UNIX trademark passed to The Open Group, a neutral industry consortium, which allows the use of the mark for certified operating systems that comply with the Single UNIX Specification (SUS). As of 2014, the Unix version with the largest installed base is Apple‘s macOS.

Standard:

In the late 1980s, an open operating system standardization effort now known as POSIXprovided a common baseline for all operating systems; IEEE based POSIX around the common structure of the major competing variants of the Unix system, publishing the first POSIX standard in 1988. In the early 1990s, a separate but very similar effort was started by an industry consortium, theCommon Open Software Environment (COSE) initiative, which eventually became the Single UNIX Specification (SUS) administered by The Open Group. Starting in 1998, the Open Group and IEEE started the Austin Group, to provide a common definition of POSIX and the Single UNIX Specification, which, by 2008, had become the Open Group Base Specification.

In 1999, in an effort towards compatibility, several Unix system vendors agreed on SVR4’s Executable and Linkable Format (ELF) as the standard for binary and object code files. The common format allows substantial binary compatibility among Unix systems operating on the same CPU architecture.

The Filesystem Hierarchy Standard was created to provide a reference directory layout for Unix-like operating systems, and has mainly been used in Linux.

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Cost

Different flavors of Unix have different cost structures according to vendors

Manufacturer

Three bigest distributions are Solaris (Oracle), AIX (IBM) & HP-UX Hewlett Packard. And Apple Makes OSX, an unix based os.

User

Unix operating systems were developed mainly for mainframes, servers and workstations except OSX, Which is designed for everyone. The Unix environment and the client-server program model were essential elements in the development of the Internet

Usage

The UNIX operating system is used in internet servers, workstations & PCs. Backbone of the majority of finance infastructure and many 24×365 high availability solutions.

File System Support (FSS)

jfs, gpfs, hfs, hfs+, ufs, xfs, zfs format

Text User Interface

Originally the Bourne Shell. Now it’s compatible with many others including BASH, Korn & C.

GUI

Initially Unix was a command based OS, but later a GUI was created called Common Desktop Environment. Most distributions now ship with Gnome.

price

some (Solaris, MacOS ) free for development use but support is available not available for free(application).

Security and threat.

A rough estimate of UNIX viruses is between 85 -120 viruses reported till date.
Because of the proprietary nature of the original Unix, users have to wait for a while, to get the proper bug fixing patch. But these are not as common.

Processor support

x86/x64, Sparc, Power, Itanium, PA-RISC, PowerPC and many others.

Example

osx, Solaris, iOS.

Architecture

is available on PA-RISC and Itanium machines. Solaris also available for x86/x64 based systems.OSX is PowerPC(10.0-10.5)/x86(10.4)/x64(10.5-10.8).

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Linux

Inspired by MINIX (a Unix-like system) and eventually after adding many features of GUI, Drivers etc, Linus Torvalds developed the framework of the OS that became LINUX in 1992. The LINUX kernel was released on 17th September, 1991

Linux is an open source, free to use operating system widely used for computer hardware and software, game development, tablet PCS, mainframes etc.

Developer

Linux is developed by Open Source development i.e. through sharing and collaboration of code and features through forums etc and it is distributed by various vendors.

Users

Everyone. From home users to developers and computer enthusiasts alike.

Usage

Linux can be installed on a wide variety of computer hardware, ranging from mobile phones, tablet computers andvideo game consoles, to mainframes and supercomputers.

File System Support (FSS)

Ext2, Ext3, Ext4, Jfs, ReiserFS, Xfs, Btrfs, FAT, FAT32, NTFS.

Text Mode Interface

BASH (Bourne Again SHell) is the Linux default shell. It can support multiple command interpreters.

GUI

Linux typically provides two GUIs,KDE and Gnome. But there are millions of alternatives such as LXDE, Xfce, Unity, Mate, twm, ect.

security and threats

Linux has had about 60-100 viruses listed till date. None of them actively spreading nowadays.
In case of Linux, threat detection and solution is very fast, as Linux is mainly community driven and whenever any Linux user posts any kind of threat, several developers start working on it from different parts of the world

Architecture

Originally developed for Intel’s x86 hardware, ports available for over two dozen CPU types including ARM