The MS-DOS (Microsoft Disk Operating System) is a single-user command operating system. The system was originated and written by computer programmer Tim Patterson and a Seattle Computer Products employee. In August 1981, Microsoft introduced GS-DOS along with Patterson and updated the system in 1994 to MS-DOS 6.22. According to the Linux Information Project, the system was considered to be one of the “most successful operating systems that have been developed to date.” Throughout the 1980’s it was identified as the dominant operating system that performed unknowingly and advanced control features. The popularity of the Apple Macintosh began to rise to the surface in 1984. This introduction eventually lead to the replacement of command line interfaces that were also used by MS-DOS. The lack of a steady GUI mutually among other programs created difficulty for users that needed to learn new programs. Many versions of the Graphical User Interfaces were generated under the authority of Microsoft Windows and its successors. MS-DOS’s own GUI was purposefully split into two separate mode systems in order to protect their self-produced program. MS-DOS has an interface that is categorized as a Command-line interface. Meaning that the language being interpreted issues commands to the program whenever something is causing some form of error. The interface operates software by allowing the user to simply respond to graphical prompts with just one click. The vast difference between the Command-line interface compared to the Graphical User Interfaces is that the CLI requires typing in prompts to receive a response. The GUI presents more of a friendly environment and allows the user to respond “too graphic images and controls” (Brainasoft p. 2). The unique values that MS-DOS has include single user, single tasking, device input of keyboard, and character user interface. Each element that makes up the operating system allows the user to smoothly interact with the program. MS-DOS is compatible with many other application extensions. The network provides abilities for a user that are much more clear compared to other PC operating systems. MS-DOS made its mark due to the variety of additional developments with similar operating systems that provide the ease of use and compatibility. In addition, another operating system that I will be discussing is the Windows systems. The Windows OPS was developed by the Microsoft Corporation in 1985. The evolution of their operating system, took an estimated 29 years to fully become developed to its full potential. It was originally classified as an extension to the previously mentioned operating system, the MS-DOS. Windows managed to incorporate users to visually be capable of displaying file contents, opening files by the click of a button, and having direct paths set up by a text prompt (Encyclopedia Britannica p. 2). Windows OPS made their first attempt at having an interface in 1985 as well, which was a 16-bit user interface (The Guardian p.3). The development of the interface was effortlessly able to be installed and ran on even the most complex programs. Their newly developed interface established more of a modern look and a faster version of user operations. Windows user interface became enormously improved within time, that by 2010 “the parallel rise of tablets and smartphones began to outsell PCs” (The Guardian p. 41). The Windows operating system consisted of a more complex and self-taught user interface. The distinctive attributes of their operating system consist of the use of right-clicking, hovering, dragging and dropping, maximizing, minimizing, closing windows and many more. Windows particularly has a wide vast of branched systems that each conduct their own special features. The amount of redesigning, improved performances, security, and quickness of operations has ultimately made Windows the first computer operating system to feature a GUI among IBM compatible PCs. Windows OPS has successfully supported programs and other operating systems to reach higher levels of advancement. Additionally, the Mac operating system was developed by Apple Inc. Apple’s marketing strategy for releasing the Macintosh was purposeful to show the ease of use is provided. Their system was introduced in 1984 “to run the company’s Macintosh line of PCs” (Encyclopedia Britannica p.1). Mac’s has definitely offered a multitude of technological advances over the centuries. The access level of Mac’s has shown the most expansion in creativity and computing services to ever exist in operating systems history. The evolution of Mac has acquired a lot of trial and error for the system itself to correctly maneuver with the user’s intentions and expectations. Mac provides a user interface that allows users to “operate the computer without having to learn advanced programming commands.” Mac’s interface includes menus, icons and a mouse. The interface was experimented numerous times solely for Apple to differentiate themselves from other systems that had basic operating tools. The company desired for their users to become familiar with the prospective Macintosh way of functions. New releases and versions of interfaces have been offered since 2011. Mac has a very innovative and fascinating operating system. The format in which Mac has built upon to exemplify their own interface has continued to attract more and more users to their products. Apple has introduced a new era of technology and features that have changed the world’s view of computer systems. The Mac System Software inevitably plays a special role in user interaction and powerful programs. The compatibility of Mac OS has originally created professional features that have shown to go beyond the average standards of the software and operation industry. Conclusively, an operating system named Linux: stores, collects and manages applications in an environment that can run the selected software. The Linux Training Academy believes that the Linux is a kernel, which also has reference to the “Linux operating system as a whole” (p. 3). A man by the name of Linus Torvalds created the system when he was enrolled at the University of Helsinki and studied computer science. Multiple developers worked on Linux around the year of 1994. The interesting thing about Linux is that it is a software that is entirely open. Linux has exceptionally traditional features for specific server applications. Linux runs their operating system with the use of UNIX-like interface written from scratch. A programming expert named, Michael Kerrisk, created the programming interface for the operating system. His ideas became timely mastered with example programs so that the user could strongly understand the “craft of system programming” (O’Reilly Media Inc. p. 1). The interface primarily works with UNIX platforms, as well as Linux’s own programming system. Furthermore, Linux is apart of 11 GUI platforms along with other operating systems. Of those GUI third-party tools include Git Extensions, GitKraken, SmartGit, GitEye, SmartGit, GitEye, gitg, ungit, git-cola, Cycling Git Tool, giggle, CodeReview, and GitAhead. These several tools are built-in individually for Linux’s browsing and application purposes. The GUI interface has more of a well-rounded precision to its system because of the level of importance LINUX seeks with their programs. In summary, Linux thrives to remain to have consistency within their operating system. The peculiar quality about Linux is that it provides a supportive platform that many of the other operating systems cannot competitively match up to. Linux dedicates their operating principles to hard-core developers looking to gain quick access from a program. Time and time again the open source operating system has found ways of enhancing and implementing much more advance contributions that satisfy both the user and programmer. Overall, the researchers learned from the evaluated operating systems have opened my knowledge of the secure development each system provides. Each PC operating system distinguishably has set standards, goals, and mechanisms that attract certain audiences. Users like the idea of having different options and versions that suit their needs of operating computers. PC operating systems will forever upgrade and improve as the world continues to evolve.