Operating Systems

Computers keep getting faster and faster, and by the start of the 1950s they had gotten so fast that it often took longer to manually load programs via punch cards than to actually run them! The solution was the operating system (or OS), which is just a program with special privileges that allows it to run and manage other programs. So today, we’re going to trace the development of operating systems from the Multics and Atlas Supervisor to Unix and MS-DOS, and take at look at how these systems heavily influenced popular OSes like Linux, Windows, MacOS, and Android that we use today.

Programs that run and manage other programs, providing special privileges on the hardware.

Operating systems

A method where computers are given batches of programs to run automatically and near-instantly, eliminating downtime.

Batch processing

Software abstractions provided by operating systems that allow programmers to interface with input and output hardware using standardized mechanisms.

Device drivers

The ability of an operating system to have multiple programs running simultaneously on a single CPU, by cleverly scheduling their execution.

Multitasking

A feature that virtualizes memory locations, allowing programs to assume their memory starts at address 0, while the actual physical location is hidden and managed by the operating system.

Virtual memory

A feature that isolates programs from each other, preventing a buggy program from corrupting the memory of other programs.

Memory protection

A feature of operating systems that allows multiple users to utilize a small fraction of the computer's resources simultaneously, ensuring fair resource allocation.

Time-sharing

An early time-sharing operating system designed to be secure, but considered over-engineered and complicated.

Multics

A lean operating system developed by Dennis Ritchie and Ken Thompson, consisting of a kernel and a wide array of useful tools.

Unix

The process of handling and resolving errors in code or software.

Error recovery

A situation where the kernel of an operating system crashes and cannot recover, often resulting in a system crash.

Kernel panic

A routine called by the kernel when a kernel panic occurs, causing the system to crash.

Panic function

An operating system developed at Bell Labs that became popular due to its simplicity and ability to run on diverse hardware.

Unix

The software that manages computer hardware and software resources, allowing users to interact with the computer.

OS (Operating System)

An operating system developed by Microsoft for early home computers, known for its simplicity and ability to fit onto a single disk.

MS-DOS (Disk Operating System)

The ability of an operating system to run multiple programs or tasks concurrently.

Multitasking

A feature of an operating system that isolates and protects the memory used by different programs, preventing one program from crashing the entire system.

Memory protection

An error screen displayed by Windows when a program or the operating system crashes.

Blue screen of death

Operating systems such as Mac OS X, Windows 10, Linux, iOS, and Android that support multitasking and have virtual and protected memory capabilities.

Modern operating systems