LinuxLinux (ˈlɪnʊks ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which includes the kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name "GNU/Linux" to emphasize the use and importance of GNU software in many distributions, causing some controversy.
Computer keyboardA computer keyboard is a peripheral input device modeled after the typewriter keyboard which uses an arrangement of buttons or keys to act as mechanical levers or electronic switches. Replacing early punched cards and paper tape technology, interaction via teleprinter-style keyboards have been the main input method for computers since the 1970s, supplemented by the computer mouse since the 1980s. Keyboard keys (buttons) typically have a set of characters engraved or printed on them, and each press of a key typically corresponds to a single written symbol.
Pointing stickA pointing stick (or trackpoint, also referred to generically as a nub or nipple) is a small analog stick used as a pointing device typically mounted centrally in a computer keyboard. Like other pointing devices such as mice, touchpads or trackballs, operating system software translates manipulation of the device into movements of the pointer or cursor on the monitor. Unlike other pointing devices, it reacts to sustained force or strain rather than to gross movement, so it is called an "isometric" pointing device.
TouchpadA touchpad or trackpad is a type of pointing device. Its largest component is a tactile sensor: an electronic device with a flat surface, that detects the motion and position of a user's fingers, and translates them to a position on a screen, to control a pointer in a graphical user interface. Touchpads are common on laptop computers, contrasted with desktop computers, where mice are more prevalent. Trackpads are sometimes used on desktops, where desk space is scarce.
TrackballA trackball mouse is a pointing device consisting of a ball held by a socket containing sensors to detect a rotation of the ball about two axes—like an upside-down ball mouse with an exposed protruding ball. Users roll the ball to position the on-screen pointer, using their thumb, fingers, or the palm of the hand, while using the fingertips to press the buttons. With most trackballs, operators have to lift their finger, thumb or hand and reposition in on the ball to continue rolling, whereas a mouse would have to be lifted itself and re-positioned.
Computer mouseA computer mouse (plural mice, also mouses) is a hand-held pointing device that detects two-dimensional motion relative to a surface. This motion is typically translated into the motion of the pointer (called a cursor) on a display, which allows a smooth control of the graphical user interface of a computer. The first public demonstration of a mouse controlling a computer system was in 1968. Mice originally used two separate wheels to directly track movement across a surface: one in the X-dimension and one in the Y.
Graphical user interfaceThe graphical user interface, or GUI (ˌdʒi:juːˈaɪ or ˈɡu:i ), is a form of user interface that allows users to interact with electronic devices through graphical icons and audio indicators such as primary notation, instead of text-based UIs, typed command labels or text navigation. GUIs were introduced in reaction to the perceived steep learning curve of command-line interfaces (CLIs), which require commands to be typed on a computer keyboard. The actions in a GUI are usually performed through direct manipulation of the graphical elements.
