A system of memory management in which the OS moves programs and data in and out of memory as needed.
A screen image of a keyboard with labeled keys that you can tap.
A major level of an operating system that includes substantive changes to the OS compared to the previous version.
user interface (UI)
The software layer, sometimes called the shell, through which the user communicates with the OS, which, in turn, communicates with the computer.
Unified Extensible Firmware Interface (UEFI
A new standard for system firmware that replaces ROM BIOS. See read-only memory basic input output system.
An operating system function in multitasking OSs that controls the focus. The user can switch between tasks by bringing an application to the foreground, which gives the focus to that application.
A mobile device that has a touch screen, no integrated keyboard (usually), is larger than a smartphone, and is much more portable than a laptop computer.
solid-state drive (SSD
A storage device that uses integrated circuits, which can be written to and read from much faster than conventional hard disk drives and optical drives.
A device that works as a cell phone but also lets you connect to the Internet, view your email, and install a variety of apps for entertainment, education, and work.
A computer that plays one or more of several important roles in a network. In all of these roles, it provides services to other computers (clients).
An operating system function that provides password-protected authentication of the user before allowing access to the local computer.
screen acceleration or screen rotation
A feature of mobile operating systems that takes advantage of the built-in hardware accelerometer in a device by rotating the image on the screen to accommodate the device’s position and allow you to read the screen.
read-only memory basic input-output system (ROM BIOS)
The original system-level PC firmware replaced in recent years by firmware that complies with a newer standard. See Unified Extensible Firmware Interface (UEFI).
random-access memory (RAM)
Memory that acts as the main memory for holding active programs.
Components of a program that are active in memory.
portable operating system
An operating system that you can use on a variety of computer system platforms, with only minor alterations required to be compatible with the underlying architecture.
personal computer (PC)
A computer running Windows or Linux.
An area of a storage device where the logical structure of a single file system may reside.
operating system (OS)
A collection of programs that provides a computer with critical functionality, such as the user interface, management of hardware and software, and ways of creating, managing, and using files.
Two or more programs (tasks) running simultaneously on a computer.
The central circuit board of a computer to which all other devices connect.
microprocessor or processor
An integrated circuit (chip) which performs the calculations, or processing, for a computer. Also called a processor or central processing unit (CPU).
A computer built around a microprocessor
An operating system function that manages and tracks the placement of programs and data in memory. Advanced operating systems, such as Windows, Linux, and Mac OS X use memory management to make optimal use of memory.
The physical chips that store programs and data. There are two basic types: random-access memory (RAM) and read-only memory (ROM).