1.4 Operating Systems

An operating system (OS) is a set of system software programs working together to oversee both hardware and application software, ensuring their proper functioning. Platforms (like Microsoft Windows) serve as the foundation for all system software, handling tasks like memory allocation, managing input and output, and organizing files. Today’s most popular business platforms include Microsoft Windows, Mac iOS, Linux, and UNIX.

File Management

One of the crucial tasks of an operating system is file management. This involves a method to store and organize files in a computer’s memory. Operating systems use a hierarchy of directories, often called folders. Think of computer files as the digital equivalents of printed documents, which were traditionally stored in file cabinets.

There are hundreds of different computer file formats that represent files created and used by various application software and system software files. Microsoft Windows visually represents its file management system using a graphical user interface (GUI) environment. You can think of this like the inner workings of a physical filing cabinet with file folders that house paper files. A file manager is a part of an operating system that displays the filing system.

Multitasking

Any task a computer performs is called a process. When a computer runs more than one process simultaneously, it’s called multitasking. Modern operating systems have multitasking capabilities, allowing a user to run application software like Microsoft Excel, Adobe Photoshop, and Microsoft Word, all at the same time.

In the past, switching between application programs was difficult and time-consuming because computers only allowed users to run one application at a time. If a user wanted to open a spreadsheet while using a word processor, they had to save the work in the word processor, close it, and then open the spreadsheet separately. This all changed with multitasking, which allows multiple application software to run at the same time.

Memory Management

Operating systems handle a computer’s memory, which includes cache, random access memory (RAM), registers, and virtual memory. In simple terms, memory stores data and information in various ways. One type is random access memory (RAM), also known as primary storage. RAM allows data to be accessed in any order without physically moving the silicone media. Virtual memory is like an endless supply of memory provided by the operating system, coordinating, tracking, and efficiently allocating the use of CPU cache, registers, RAM, and disk storage.

Disk Management

An operating system (OS) is responsible for reading and writing data to a disk, often a hard drive. Disk storage refers to non-volatile, secondary storage on a physical device like a hard drive (or cloud drive), solid state drive, or optical disk with a read/write apparatus. The OS needs to save information to a disk efficiently so that files can be read quickly and, consequently, efficiently. On a Microsoft platform like Windows, a common method to read/write data is to generate a table of contents for the disk, known as a file allocation table (or NTFS) or FAT. The FAT guides the read/write arm of the hard drive to the location of data and accesses it when the user requests it.