Technical Terms

Here is a list of technical terms old and new. It's a good list and worth having a look at if you are at all interested in the world of computing and computer programming.

I humbly acknowledge Alastair Gourlay for originally authoring this list in the book 'Games for your VIC20" I have simply expanded upon the excellent work that he has done.

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Term	Meaning
Accumulator	The place within the computer in which arithmetic computations are performed and where the results of these computations are stored.
Algorithm	The series of steps the computer follows to solve a particular problem.
Alphanumeric	This term is usually used in relation to a keyboard, as in "it is an alphanumeric keyboard", which means that the keyboard has letters as well as numbers. It is also used to refer to the "character set" of the computer. The character set comprises the numbers and letters the computer can print on the screen.
ALU	(Arithmetic/Logic Unit)the part of the computer which does arithmetic (such as addition, subtraction) and where decisions are made.
AND	A Boolean logic operation that the computer uses in its decision-making process. It is based on Boolean algebra, a system developed by mathematician George Boole (1815-64). In Boolean algebra the variables of an expression represent a logical operation such as OR and NOR.
ASCII	Stands for American Standard Code for Information Exchange, the most widely used encoding system for English language alphanumerics. There are 128 upper and lower case letters, digits and some special characters. ASCII converts the symbols and control instructions into seven-bit binary combinations.
Assembler	A program which converts other programs written in assembly language into machine code (which the computer can understand directly). Assembly language is a low level programming language which uses easily memorized combinations of two or three letters to represent a particular instruction which the assembler then converts so the machine can understand it. Examples of these are ADD(add), and SUB (subtract). A computer programmed in assembly language tends to work more quickly than one programmed in a higher level language such as BASIC.
BASIC	An acronym for Beginners All-Purpose Symbolic Instruction Code. It is the most widely used computer language in the microcomputer field. Although it has been criticized by many people, it has the virtue of being very easy to learn. A great number of BASIC statements resemble ordinary English.
Baud	Named after Baudot, a pioneer of telegraphic communications. Baud measures the rate of transfer of information and is approximately equal to one bit per second.
BCD	An abbreviation for Binary Coded Decimal.
Benchmark	A test against which certain functions of the computer can be measured. There are a number of so- called "standard Benchmark tests," but generally these only test speed. This is rarely the aspect of a microcomputer that is of most interest to the potential buyer.
Binary	A numbering system that uses only zeros and ones.
Bit	An abbreviation for Binary Digit. This is the smallest unit of information a computer circuit can recognize.
Boolean Algebra	The system of algebra developed by mathematician George Boole which uses algebraic notation to express logical relationships (see AND).
Bootstrap	A short program or routine which is read into the computer when it is first turned on. It orients the computer to accept the longer, following program.
Bug	An error in a computer program which stops the program from running properly. Although it is generally used to mean only a fault or an error in a program, the term bug can also be used for a fault in the computer hardware.
Bus	A number of conductors used for transmitting signals such as data instructions, or power in and out of a computer.
Byte	A group of binary digits which make up a computer word. Eight is the most usual number of bits in a byte.
CAl	Computer Assisted Instruction.
CAL	Computer Assisted Learning. The term is generally used to describe programs which involve the learner with the learning process.
Chip	The general term for the entire circuit which is etched onto a small piece of silicon. The chip is, of course, at the heart of the microcomputer.
Clock	The timing device within the computer that synchronizes its operations.
COBOL	A high level language derived from the words Common Business Orientated Language. COBOL is designed primarily for filing and record-keeping.
Comparator	A device which compares two things and produces a signal related to the difference between the two.
Compiler	A computer program that converts high level programming language into binary machine code so the computer can handle it.
Complement	A number which is derived from another according to specified rules.
Computer	A device with three main abilities or functions: To accept data To solve problems To supply results
CPU	Stands for Central Processing Unit. This is the heart of the computer's intelligence, where data is handled and instructions are carried out.
Cursor	A character which appears on the TV screen when the computer is operating. It shows where the next character will be printed. On a computer there are usually "cursor control keys" to allow the user to move the cursor around the screen.
Data	Information in a form which the computer can process.
Debug	The general term for going through a program and correcting any errors in it, that is, chasing down and removing bugs (see Bug).
Digital Computer	A computer which operates on information which is in a discrete form.
Disk/Disc	This is a magnetically sensitized plastic disk, a little smaller than a single play record. This is used for storing programs and for obtaining data. Disks are considerably faster to load than a cassette of the same length program. The disk can be searched very quickly while a program is running for additional data.
Display	The visual output of the computer, generally on a TV or monitor screen.
Dot Matrix Printer	A printer which prints either the listing of a program or that which is displayed on the TV screen. Each letter and character is made up of a number of dots. The higher the number of dots per character the finer the resolution of the printer.
Dynamic Memory	A memory unit within the computer which "forgets" its contents when the power is turned off.
Editor	This term is generally used for the routine within the computer which allows you to change lines of a program while you are writing it.
EPROM	Stands for Erasable Programmable Read-Only Memory. This is like the ROM in the computer, except that it is fairly easy to load material into an EPROM and it doesn't disappear when you turn the power off. EPROMs must be placed in a strong ultra violet light to erase them.
Error Message	The information given by a computer where there is a fault in the coding during a part of a program, usually shown by the computer stopping, and printing a word, or a word and numbers, or a combination of numbers only, at the bottom of the screen. This tells you what mistake has been made. Common mistakes include using the letter 0 instead of zero in a line, or leaving out a pair of brackets, or one of the brackets, in an expression, or failing to define a variable.
File	A collection of related items of information organized in a systematic way.
Floppy Disk	A relatively cheap form of magnetic disk used for storing computer information, and so named because it is quite flexible (see Disk/Disc).
Flow Chart	A diagram drawn up before writing a program, in which the main operations are enclosed within rectangles or other shapes and connected by lines, with arrows to represent loops, and decisions written at the branches. It makes writing a program much easier because traps such as infinite loops, or non-defined variables can be caught at an early stage. It may not be worth writing a flow chart for very short programs, but generally a flow chart aids in creating programs.
Firmware	There are three kinds of "ware" in computers: software "temporary" programs; hardware like the ROM which contains permanent information; and firmware in which the information is relatively permanent, as in an EPROM (see EPROM).
Flip-Flop	A circuit which maintains one electrical condition until changed to the opposite condition by an input signal.
FORTRAN	An acronym for FORmula TRANslation, this is a high-level, problem orientated computer language for scientific and mathematical use.
Gate	An electrical circuit which, although it may accept one or more incoming signals, only sends out a single signal.
Graphics	Pictorial information as opposed to letters and numbers.
Hard Copy	Computer output which is in permanent form.
Hardware	The physical parts of the computer (also see software and firmware).
Hexadecimal	(Hex) A numbering system to the base sixteen. The digits zero to nine are used, as well as the letters A, B, C, D, E and F to represent numbers. A equals 10, B equals 11, C equals 12, and so on. Hex is often used by microprocessor users.
Hex Pad	A keyboard designed specifically for entering hexadecimal notation.
High Level Language	A programming language which allows the user to talk to the computer more or less in English. In general, the higher the level of the language (that is, the closer it is to English), the longer it takes for the computer to translate it into a language it can use. Lower level languages are far more difficult for human operators but are generally executed far more quickly.
Hosting	In order to publish a website online, you need a Web host. The Web host stores all the pages of your website and makes them available to other computers connected to the Internet for them to see.
Input	The information fed into the computer via a keyboard, a microphone, a cassette or a disk.
Input/Output	(I/0 Device) A device which accepts information or instructions from the outside world, relays it to the computer, and then, after processing, sends the information out in a form suitable for storing, or in a form which could be understood by a human being.
Instruction	Data which directs a single step in the processing of information by the computer (also known as a command).
Integrated Circuit	A complete electronic circuit imprinted on a semiconductor surface.
Interface	The boundary between the computer and a peripheral such as a printer.
Interpreter	A program which translates the high level language fed in by the human operator, into a language which the machine can understand.
Inverter	A logic gate that changes the signal being fed in, to the opposite one.
Interactive Routine	Part of a program which is repeated over and over again until a specified condition is reached.
Jump Instruction	An instruction which tells the computer to go to another part of the program, when the destination of this move depends on the result of a calculation just performed.
Keyword	The trigger word in a line of programming, usually the first word after the line number. Keywords include STOP, PRINT and GOTO.
Kilobyte (K)	This relates to the size of the memory. Memory is usually measured in 4K blocks. 1K contains 1,024 bytes.
Language	Computer languages are divided into three sections: high level languages, such as BASIC, which are reasonably close to English and fairly easy for humans to use; low level languages, such as Assembler, that use short phrases which have some connection with English (ADD for add and RET for return, for instance); and machine code which communicates more or less directly with the machine.
LC	This stands for Liquid Crystal Diode. Some computers such as the TRS-80 Pocket Computer use an LCD display.
LED	This stands for Light Emitting Diode. The bright red numbers which are often used on watch or clock displays are made up of LEDs.
Logic	The mathematical form of a study of relationships between events.
Loop	A sequence of instructions within a program which is performed over and over again until a particular condition is satisfied.
Machine Language	Or Machine Code. An operation code which can be understood and acted upon directly by the computer.
Magnetic Disk	See Disk and Floppy Disk.
Mainframe	Computers are generally divided into three groups, and the group a computer falls into depends more or less on its size. The TS-1000 you are using is a microcomputer; medium sized computers are known as minicomputers; and the giant computers that you sometimes see in science fiction movies are mainframe computers. Until 15 years ago mainframe computers were, in practical terms, the only ones available.
Memory	There are two types of memory within a computer. The first is called ROM (read-only memory); this is the memory that comes already programmed on the computer, which tells the computer how to make decisions and how to carry out arithmetic operations. This memory is unaffected when you turn the computer off. The second type is RAM (random access memory). This memory holds the program you type in at the keyboard or send in via a cassette or disk. In most computers the computer "forgets" what is in RAM when you turn the power off.
Microprocessor	The heart of any computer. It requires peripheral unit interfaces, such as a power supply and input and output devices, to act as a microcomputer.
MODEM	Stands for Modulator Demodulator. This is a device which allows two computers to talk to each other over the telephone. The computers usually use a cradle in which a telephone receiver is placed.
Monitor	This has two meanings in computer terms. One meaning is a television-like display. A monitor has no facility for tuning television programs, and usually the picture produced on a monitor is superior to that produced by an ordinary television. The second meaning of a monitor relates to ROM. The monitor of a computer is described as the information it has built in when you buy it. This information allows it to make decisions and carry out arithmetic computations.
Motherboard	A framework to which extra circuits can be added. These extra circuits often give the computer facilities which are not built-in, such as that of producing sound or of controlling a light pen.
MPU	An abbreviation for Microprocessor Unit.
Nano-second	A nano-second is one thousand billionth of a second, the unit of speed in which a computer or a memory chip is often rated.
Non-Volatile Memory	Memory which is not lost when the computer is turned off. Some of the smaller computers such as the TRS-80 Pocket Computer have non-volatile memory. The batteries hold the program you enter for several hundred hours.
Not	A Boolean logic operation that changes a binary digit into its opposite.
Null String	A string which contains no characters. It is shown in the program as two double quote marks, without anything between them.
Numeric	Pertaining to numbers as opposed to letters (that is, alphabetic). Many keyboards are described as being alphanumeric which means both numbers and letters are provided.
Octal	A numbering system which uses eight as the base, and the digits 0, 1, 2, 3, 4, 5, 6 and 7. The Octal system is not used very much nowadays in microcomputer fields. The Hexadecimal system is more common (see Hexadecimal).
Operating System	The software or firmware generally provided with the machine that allows you to run other programs.
OR	An arithmetic operation that returns a 1, if one or more inputs are 1.
Oracle	A method of sending text messages with a broadcast television signal. A teletext set is required to decode the messages.
Output	Information or data fed out by the computer to such devices as a TV-like screen, a printer or a cassette tape. The output usually consists of the information which the computer has produced as a result of running a program.
Overflow	A number too large or too small for the computer to handle.
Pad	See Keypad.
Page	Often used to refer to the amount of information needed to fill one TV screen, so you can talk about seeing a page of a program, the amount of the listing that will appear on the screen at one time.
PASCAL	A high level language.
Peripheral	Anything which is hooked onto a computer, for control by the computer, such as a disk unit, a printer or a voice synthesizer.
Port	A socket through which information can be fed out of or in to a computer.
Prestel	The British telecom name for a system of calling up pages of information from a central computer via the telephone and displaying them on a television screen. A similar commercial version in the United States is known as The Source.
Program	In computer terms program has two meanings. One is the list of instructions that you feed into a computer, and the second is used as a verb; as in lito program a computer.
PROM	Stands for Programmable Read Only Memory. This is a device which can be programmed, and once it is then the program is permanent (see also EPROM and ROM).
Random Access Memory	(RAM) The memory within a computer which can be changed at will by the person using the computer. The contents of RAM are usually lost when a computer is turned off. RAM is the memory device that stores the program that you type in and also stores the results of calculations in progress.
Read-Only Memory	(ROM) In contrast to RAM, information in ROM cannot be changed by the user of the computer, and the information is not lost when the computer is turned off. The data in ROM is put there by the manufacturers and tells the computer how to make decisions and how to carry out arithmetic computations. The size of ROM and RAM is given in the unit K (see K).
Recursion	The continuous repetition of a part of the program.
Register	A specific place in the memory where one or more computer words are stored during operations.
Reserved Word	A word that you cannot use for a variable in a program because the computer will read it as something else. An example is the word TO. Because TO has a specific computer meaning, most computers will reject it as a name for a variable. The same goes for words like FOR, GOTO and STOP.
Routine	This word can be used as a synonym for program, or can refer to a specific section within a program (see also Subroutine).
Second Generation	This has two meanings. The first applies to computers using transistors, as opposed to first generation computers which used valves. Second generation can also mean the second copy of a particular program; subsequent generations are degraded by more and more noise.
Semiconductor	A material that is usually an electrical insulator but under specific conditions can become a conductor.
Serial	Information which is stored or sent in a sequence, one bit at a time.
Signal	An electrical pulse which is a conveyor of data.
Silicon Valley	The popular name given to the area in California where many semiconductor manufacturers are located.
SNOBOL	A high level language.
Software	The program which is entered into the computer by a user which tells the computer what to do.
Software Compatible	This refers to two different computers which can accept programs written for the other.
Static Memory	A non-volatile memory device which retains information so long as the power is turned on, but does not require additional boosts of power to keep the memory in place.
Subroutine	Part of a program which is often accessed many times during the execution of the main program. A subroutine ends with an instruction to go back to the line after the one which sent it to the subroutine.
Teletext	Information transmitted in the top section of a broadcast television picture. It requires a special set to decode it to fill the screen with text information. Teletext messages can be transmitted by cable or over phone lines. Examples of this are the Prestel service in Britain and The Source in the United States.
Teletype	A device like a typewriter which can send information and also receive and print it.
Terminal	A unit independent of the central processing unit. It generally consists of a keyboard and a cathode ray display.
Time Sharing	A process by which a number of users may have access to a large computer which switches rapidly from one user to another in sequence, so each user is under the impression that he or she is the sole user of the computer at that time.
Truth Table	A mathematical table which lists all the possible results of a Boolean logic operation, showing the results you get from various combinations of inputs.
UHF	Ultra High Frequency (300-3000 megaHertz).
URL	A uniform resource locator, abbreviated URL, also known as web address, is a specific character string that constitutes a reference to a resource. In most web browsers, the URL of a web page is displayed on top inside an address bar.
Ultra Violet Erasing	Ultra violet light must be used to erase EPROMs (see EPROM).
Variable	A letter or combination of letters and symbols which the computer can assign to a value or a word during the run of a program.
VDU	An abbreviation for Visual Display Unit.
Volatile	Refers to memory which "forgets" its contents when the power is turned off.
Web Site	A Web site is a related collection of World Wide Web (WWW) files that includes a beginning file called a home page. A company or an individual tells you how to get to their Web site by giving you the address of their home page. From the home page, you can get to all the other pages on their site.
Word	A group of characters, or a series of binary digits, which represent a unit of information and occupy a single storage location. The computer processes a word as a single instruction.
Word Processor	A highly intelligent typewriter which allows the typist to manipulate text, to move it around, to justify margins and to shift whole paragraphs if necessary on a screen before outputting the information onto a printer. Word processors usually have memories, so that standard letters and the text of letters, written earlier, can be stored.