An operating system is the program that acts as the backbone for all other programs installed on to an IT system, whether it be phone, computer, tablet or laptop. It manages crucial functions of the machine, such as how the computer runs, and how various types of software installed on the machine interacts with the hardware. The two most commonly used types of operating systems are Mac OS and Microsoft Windows. Mac OS is a product created by Apple, famous for its iPhones and MacBooks, which comes preloaded on every Apple Mac computer, phone and laptop. Although Mac OS accounts for only roughly 10% of the world’s usage of operating systems, it is increasingly popular due to its advertising, use in media and modern & appealing design. Microsoft Windows, however, continues to be the most widely used operating system worldwide, with an estimated 80% of supply to the world’s IT systems. On a majority of new computers (with the obvious exception to Apple products), Windows comes pre-loaded, a factor contributing to its worldwide status. Windows may also be seen as the original operation system, beginning in the mid 80s and continuing to expand from then to now as technology has progressed.