Is This Time For Reversible Computers

Rugged Computer ... Construction Virtually all rugged computers share an underlying design philosophy of providing a controlled environment for the installed electronics...

Computer ... Conventionally a computer consists of some form of memory, at least one element that carries out arithmetic and logic operations, and a sequencing and control unit that can change the order of operations based on the information that is stored. Peripheral devices allow information to be entered from an external source, and allow the results of operations to be sent out...

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...

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...

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...

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...

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...

Personal Computer Hardware ... EISA Micro Channel architecture ISA: expansion card slot format obsolete in PCs, but still used in industrial computers... Most modern computers have hardware support for sound integrated in the motherboard chipset but some users prefer to install a separate sound card as an upgrade...

Computer Network ... Networks may be classified according to a wide variety of characteristics such as the medium used to transport the data, communications protocol used, scale, topology, and organizational scope. Communications protocols define the rules and data formats for exchanging information in a computer network, and provide the basis for network programming...

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...

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)...

Software Bug ... Bugs trigger errors that can in turn have a wide variety of ripple effects, with varying levels of inconvenience to the user of the program. Some bugs have only a subtle effect on the program's functionality, and may thus lie undetected for a long time...

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...

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...

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...

Computer Programming ... There is an ongoing debate on the extent to which the writing of programs is an art, a craft or an engineering discipline. In general, good programming is considered to be the measured application of all three, with the goal of producing an efficient and evolvable software solution (the criteria for "efficient" and "evolvable" vary considerably)...

Motherboard ... The most popular computers such as the Apple II and IBM PC had published schematic diagrams and other documentation which permitted rapid reverse-engineering and third-party replacement motherboards... Usually intended for building new computers compatible with the exemplars, many motherboards offered additional performance or other features and were used to upgrade the manufacturer's original equipment...

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...

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...

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"...

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...

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...