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Software ... Computer software is so called to distinguish it from computer hardware, which encompasses the physical interconnections and devices required to store and execute (or run) the software. At the lowest level, execunguage consists of groups of binary values signifying processor instructions that change the state of the computer from its preceding state...
Laptop ... As portable computers became smaller, lighter, cheaper, more powerful and as screens became larger and of better quality, laptops became very widely used for all sorts of purposes, by all sorts of people...
Computer Multitasking ... The expression 'time sharing' was usually used to designate computers shared by interactive users at terminals, such as IBM's TSO, and VM/CMS In real-time systems, some waiting tasks are guaranteed to be given the CPU when an external event occurs... The term time-sharing is no longer commonly used, having been replaced by simply multitasking, and by the advent of personal computers and workstations rather than shared interactive systems...
Central Processing Unit ... On personal computers and small workstations, the CPU is housed in a single silicon chip called a microprocessor...
Konrad Zuse ... Zuse was also noted for the S2 computing machine, considered the first process-controlled computer. He founded one of the earliest computer businesses in 1941, producing the Z4, which became the world's first commercial computer...
Netbook ... More recently, Psion's now-discontinued netBook line, the OLPC XO-1 (initially called US$100 laptop) and the Palm Foleo were all small, portable, network-enabled computers...
CPU Design ... CPUs designed for lower performance markets might lessen the implementation burden by: Acquiring some of these items by purchasing them as intellectual property Use control logic implementation techniques (logic synthesis using CAD tools) to implement the other components - datapaths, register files, clocks Common logic styles used in CPU design include: Unstructured random logic Finite-state machines Microprogramming (common from 1965 to 1985) Programmable logic array (common in the 1980s, no longer common) Device types used to implement the logic include: Transistor-transistor logic Small Scale Integration logic chips - no longer used for CPUs Programmable Array Logic and Programmable logic devices - no longer used for CPUs Emitter-coupled logic (ECL) gate arrays - no longer common CMOS gate arrays - no longer used for CPUs CMOS ASICs - what's commonly used today, they're so common that the term ASIC is not used for CPUs Field-programmable gate ar...
Computer Data Storage ... In contemporary usage, 'memory' usually refers to semiconductor storage read-write random-access memory, typically DRAM (Dynamic-RAM). Memory can refer to other forms of fast but temporary storage...
Internet Privacy ... Internet privacy forms a subset of computer privacy. A number of experts within the field of Internet security and privacy believe that privacy doesn't exist; "Privacy is dead – get over it" according to Steve Rambam, private investigator specializing in Internet privacy cases...
Arithmetic Logic Unit ... Early computers used a wide variety of number systems, including ones' complement, two's complement sign-magnitude format, and even true decimal systems, with various representation of the digits... Therefore, while even the simplest computer can calculate the most complicated formula, the simplest computers will usually take a long time doing that because of the several steps for calculating the formula...
Desktop Replacement Computer ... Desktop replacement computers are also often used with a port replicator, to fully enjoy the desktop comfort... Design features Modern desktop replacements generally perform better than traditional laptop-style computers as their size allows the inclusion of more powerful components... However, these advantages generally come at a price premium, with many computers in this class costing as much as two desktop computers with similar specifications...
Personal Digital Assistant ... The first PDA was released in 1986 by Psion, the Organizer II. Followed by Psion's Series 3, in 1991, which began to resemble the more familiar PDA style...
Packet Switching ... Packet switching contrasts with another principal networking paradigm, circuit switching, a method which sets up a limited number of dedicated connections of constant bit rate and constant delay between nodes for exclusive use during the communication session. In case of traffic fees (as opposed to flat rate), for example in cellular communication services, circuit switching is characterized by a fee per time unit of connection time, even when no data is transferred, while packet switching is characterized by a fee per unit of information...
Internet Protocol Suite ... The Internet protocol suite has four abstraction layers, each with its own protocols. From lowest to highest, the layers are: The link layer contains communication technologies for a local network...
Periphere Computer-Systeme ... In addition to UNIX computers, PCS also manufactured industrial terminals. Eventually, PCS was bought out by Mannesmann-Kienzle, which in turn was bought out by Ken Olsen to become part of DEC, Digital Equipment Corporation...
Colossus Computer ... The Colossus computers were used to help decipher teleprinter messages which had been encrypted using the Lorenz SZ40/42 machine—British codebreakers referred to encrypted German teleprinter traffic as "Fish" and called the SZ40/42 machine and its traffic "Tunny"...
Unconventional Computing ... Some mechanical computers have a theoretical or didactic relevance, such as billiard-ball computers or hydraulic ones,... Light (optical computing) Computers can manipulate information as light (rather than electricity or billiard balls)...
Programming Language ... The earliest programming languages predate the invention of the computer, and were used to direct the behavior of machines such as Jacquard looms and player pianos. Thousands of different programming languages have been created, mainly in the computer field, with many more being created every year...
High-level Programming Language ... The first high-level programming language designed for computers was Plankalkül, created by Konrad Zuse...
Wi-Fi ... A device that can use Wi-Fi (such as a personal computer, video game console, smartphone, tablet, or digital audio player) can connect to a network resource such as the Internet via a wireless network access point. Such an access point (or hotspot) has a range of about 20 meters (65 feet) indoors and a greater range outdoors...
Smartbook ... A German company sold laptops under the brand Smartbook and held a trademark for the word in many countries (not including some big markets like United States, China, Japan, or India). It acted to preempt others from using the term smartbook to describe their products...
Computer Program ... Computer source code is often written by computer programmers. Source code is written in a programming language that usually follows one of two main paradigms: imperative or declarative programming...
Programmer ... Computer programmers write, test, debug, and maintain the detailed instructions, called computer programs, that computers must follow to perform their functions...
History Of Laptops ... Compaq SLT/286 By the end of the 1980s, laptop computers were becoming popular among business people...
Microprocessor ... General-purpose microprocessors in personal computers are used for computation, text editing, multimedia display, and communication over the Internet...