Reverse Polish notation (RPN), also known as reverse Łukasiewicz notation, Polish postfix notation or simply postfix notation, is a mathematical notation in which operators follow their operands, in contrast to prefix or Polish notation (PN), in which operators precede their operands. The notation does not need any parentheses for as long as each operator has a fixed number of operands.
A one-instruction set computer (OISC), sometimes referred to as an ultimate reduced instruction set computer (URISC), is an abstract machine that uses only one instruction – obviating the need for a machine language opcode. With a judicious choice for the single instruction and given arbitrarily many resources, an OISC is capable of being a universal computer in the same manner as traditional computers that have multiple instructions. OISCs have been recommended as aids in teaching computer architecture and have been used as computational models in structural computing research. The first carbon nanotube computer is a 1-bit one-instruction set computer.
The Z3 was a German electromechanical computer designed by Konrad Zuse in 1938, and completed in 1941. It was the world's first working programmable, fully automatic digital computer. The Z3 was built with 2,600 relays, implementing a 22-bit word length that operated at a clock frequency of about 5–10 Hz. Program code was stored on punched film. Initial values were entered manually.
Excess-3, 3-excess or 10-excess-3 binary code, shifted binary or Stibitz code is a self-complementary binary-coded decimal (BCD) code and numeral system. It is a biased representation. Excess-3 code was used on some older computers as well as in cash registers and hand-held portable electronic calculators of the 1970s, among other uses.
In mathematical logic and theoretical computer science, a register machine is a generic class of abstract machines used in a manner similar to a Turing machine. All models of register machines are Turing equivalent.
ARD is a joint organisation of Germany's regional public-service broadcasters. It was founded in 1950 in West Germany to represent the common interests of the new, decentralised, post-war broadcasting services – in particular the introduction of a joint television network.
Westdeutscher Rundfunk Köln, shortened to WDR, is a German public-broadcasting institution based in the Federal State of North Rhine-Westphalia with its main office in Cologne. WDR is a constituent member of the consortium of German public-broadcasting institutions, ARD. As well as contributing to the output of the national television channel Das Erste, WDR produces the regional television service WDR Fernsehen and six regional radio networks.
The MC14500B Industrial Control Unit (ICU) is a CMOS one-bit microprocessor designed by Motorola for simple control applications in 1977.
The Z1 was a motor-driven mechanical computer designed by German inventor Konrad Zuse from 1936 to 1937, which he built in his parents' home from 1936 to 1938. It was a binary electrically driven mechanical calculator with limited programmability, reading instructions from punched celluloid film.
CARDIAC (CARDboard Illustrative Aid to Computation) is a learning aid developed by David Hagelbarger and Saul Fingerman for Bell Telephone Laboratories in 1968 to teach high school students how computers work. The kit consists of an instruction manual and a die-cut cardboard "computer".
The ZEBRA was one of the first computers to be designed in the Netherlands, and one of the first Dutch computers to be commercially available. It was designed by Willem van der Poel of the Netherlands Post, Telegraph and Telephone, and first delivered in 1958. The production run consisted of fifty-five machines, manufactured and marketed by the British company Standard Telephones and Cables, Ltd.
The Digi-Comp I was a functioning, mechanical digital computer sold in kit form. It was originally manufactured from polystyrene parts by E.S.R., Inc. starting in 1963 and sold as an educational toy for US$4.99.
Rockpalast is a German music television show that broadcasts live on German television station Westdeutscher Rundfunk (WDR). Rockpalast started on January 22, 1976 and continues to this day. Hundreds of rock, heavy metal and jazz bands have performed on Rockpalast. Some acts were recorded for broadcast and for retail sale. All-night marathon shows called “Rock Night” (Rocknacht) were produced once or twice a year from 1977 through 1986 and simulcast throughout Europe via the Eurovision network of TV broadcasters, thereby reaching around 25 million listeners on average. Rockpalast is involved in several German pop, rock and underground music festivals, once sponsoring the Bizarre-Festival.
A counter machine is an abstract machine used in a formal logic and theoretical computer science to model computation. It is the most primitive of the four types of register machines. A counter machine comprises a set of one or more unbounded registers, each of which can hold a single non-negative integer, and a list of arithmetic and control instructions for the machine to follow. The counter machine is typically used in the process of designing parallel algorithms in relation to the mutual exclusion principle. When used in this manner, the counter machine is used to model the discrete time-steps of a computational system in relation to memory accesses. By modeling computations in relation to the memory accesses for each respective computational step, parallel algorithms may be designed in such a matter to avoid interlocking, the simultaneous writing operation by two threads to the same memory address.
There are many variants of the counter machine, among them those of Hermes, Ershov, Péter, Minsky, Lambek, Shepherdson and Sturgis, and Schönhage. These are explained below.
The Olivetti Programma 101, also known as Perottina or P101, is one of the first "all in one" commercial desktop programmable calculators, although not the first. Produced by Italian manufacturer Olivetti, based in Ivrea, Piedmont, and invented by the Italian engineer Pier Giorgio Perotto, the P101 used many features of large computers of that period. It was launched at the 1964 New York World's Fair; volume production started in 1965. A futuristic design for its time, the Programma 101 was priced at $3,200 (equivalent to $29,700 in 2022). About 44,000 units were sold, primarily in the US.
In computer architecture, 1-bit integers or other data units are those that are 1 bit wide. Also, 1-bit central processing unit (CPU) and arithmetic logic unit (ALU) architectures are those that are based on registers of that size.
WDR Computerclub was the first television broadcast in West Germany of the Westdeutscher Rundfunk (WDR) that dealt solely with the issues of computer and technology. It began its first broadcasting in 1981 under the name eff-eff, was later renamed to WDR Computerclub, and was hosted until 2003 by Wolfgang Back and Wolfgang Rudolph.
Wolfgang Händler was a German mathematician, pioneering computer scientist and professor at Leibniz University Hannover and University of Erlangen–Nuremberg known for his work on automata theory, parallel computing, artificial intelligence, man-machine interfaces and computer graphics.
Norbert Ryska is a German mathematician and museum director. Ryska worked from 1976 to 1992 as an employee of Nixdorf Computer AG in the R&D department. Until 1996 as managing director and project manager on behalf of the Nixdorf Foundations mainly responsible for the construction of the Heinz Nixdorf MuseumsForum (HNF). From 1996 to 2013, Ryska was the managing director for the museum and technology departments of the HNF.
