- windows, Mac OSX, Linux, Android, and iOS are all examples of operating systems. that are widely used today. An operating system or OS. enables us to interact with the computer and run applications. OS's do this by handling a number of important tasks. First of all, they provide a user interface or UI. enabling users to interact with a computer. There are two types of UI GUIs or graphical user interfaces. provide a visual interface including tiles, icons and menus. This type of interface is the most common for PCs and mobile devices. CLIs or command line interfaces use text only. The user enters commands and receives feedback from the OS. all in text format. Although CLIs are faster to use, more flexible and. less demanding on memory, they normally require expert knowledge to use. Second OS manage the CPU. Each time a piece of software opens the OS, finds the program files. on the storage, drive, loads them into main memory and instructs. the CPU to start executing the program from the beginning. CPUs can only access one program at a time. To overcome this limitation and enable multitasking. OS's moves and store several programs into the RAMs simultaneously. This allows programs to be in one of three States. running weighting or runnable. The OS decides the best way to swap between these States. because memory is a limited resource. There is a finite number of programs that can be moved onto the RAM. OS's manage how this memory is used. They decide for instance how memory is shared between processes. and what happens when there is not enough main memory for a task. OS also manage peripheral devices. Each device comes with its own rules that it takes, how it transmits data values between itself and the computer. It's machine code. Additionally, OS's use device. drivers to manage connections, putting devices to sleep. for instance when they aren't being used. OS's organize files and directories determining how files are stored, deleted, bred, found and repaired. The files are stored in a hierarchy structured much like a library, windows file Explorer and Mac OSX finder of both programs. that take advantage of these hierarchies. Finally, OS's use applications called utilities, enabling the user to back up and format that computer. as well as keeping it safe. For example, through encryption. So now you know how important OS's are. They provide a user interface, manage the CPU. enable multitasking, manage memory and peripherals, organize files and directories, and apply utilities with formatting and security. Most of the work done by OS's is invisible. Many users won't even be aware when they are using one, but without OS's as you've just seen, most of us could not take advantage of the amazing. benefits the computer technology has to offer.