Introduction to Operating Systems and Evolution

This set of vocabulary flashcards covers the fundamental objectives, functions, historical evolution, and specific architectural components of major operating systems including Windows, UNIX, Linux, and Android.

Operating System (OS)

A system that utilizes hardware resources of one or more processors to provide services to users, manages secondary memory and I/O devices, and coordinates hardware use among various programs.

Serial Processing

A historical processing method where programs in machine code were loaded via input devices like card readers, often resulting in wasted processing time due to scheduling and set-up time problems.

Simple Batch Systems

Developed in the mid-1950s by General Motors Research Laboratories to improve processor utilization by processing jobs in bulk using a resident monitor.

Multi-programmed Batch Systems

Systems that keep several ready-to-run jobs in main memory to allow the processor to handle multiple jobs at a time, requiring memory management and scheduling algorithms.

Time-sharing Systems

Systems that allow multiple users to simultaneously access the system through terminals, where each user is allocated $1/n$ of the compute capacity if $n$ users are active.

Compatible Time-Sharing System (CTSS)

One of the first time-sharing operating systems, developed at the Massachusetts Institute of Technology (MIT) by Project MAC for the IBM 709 computer system.

Windows Executive

A component of the Windows core OS running in kernel-mode that contains the core modules and services for specific functions.

Windows Kernel

The component of the Windows OS that specifically controls the execution of the processor.

Hardware Abstraction Layer (HAL)

A Windows kernel component that isolates the operating system from platform-specific hardware variances.

Classic UNIX OS

Developed at Bell Labs and initially called Uniplexed Information and Computing Service (UNICS); it was partly written in assembly and later converted to C language.

System V Release 4 (SVR4)

A modern UNIX implementation developed to provide a uniform platform for commercial deployment on processors ranging from 32-bit to supercomputers.

Berkeley Software Distribution (BSD)

An implementation that played an important role in the development of UNIX OS design theory and the release of commercial UNIX products.

Linux OS

A free open-source variant of the UNIX operating system written by Linus Torvalds, composed of independent blocks called loadable modules.

Loadable Modules

Object files in Linux that can be linked and unlinked from the kernel at runtime, characterized by dynamic linking and being stackable.

Android OS

A software stack including a modified Linux kernel, middleware, and key applications; originally initiated by Android, Inc. and bought by Google in 2005.

Android Open-Source Project (AOSP)

The source code used by a community of developers to develop and distribute modified versions of the Android operating system.