Section: Vocabulary

Vocabulary / Main Concepts

Computer

In general, a universal information manipulator

Universal

Capable of doing any kind of operation to any kind of information. Today's computers are not quite universal, but they come closer to being universal than any other machine yet invented.

Information

The stuff a computer works with. A computer can work with any kind of data that can eventually be translated into binary (one/zero) format.

Manipulator

A machine that processes something. A computer is unique because it can process information, not just physical quantities like most machines.

Data

Another term for information. Some computer scientists refer to all the stuff a computer deals with as data, and the stuff that has some meaning as information. Note that "data" is a plural noun. The singular form is "datum."

Digital

An information coding scheme based on numeric representation of values. Digital information is characterized by limited precision, but strong accuracy.

Analog

An information coding scheme based on physical analogies between a value and some physical object. Analog information is characterized by infinite precision but limited accuracy.

Precision

How small and close together the units of measure are. A teaspoon is more precise than a dump truck. A scalpel is more precise than a chain saw.

Accuracy

How faithfully a recording scheme captures the original. How close something is to perfection. A photocopy is more accurate than a handrwitten transcript.

Binary

Relating to the value two. The binary system is a numbering system in base two. Anything that has only two possible values is thought of as binary. A light switch a good example of a binary device.

Base 10

The numbering system we are used to using. The digits all represent powers of 10. Each digit can hold one of 10 possible values (including zero), and 9 is the highest possible value in each digit.

Base 2

Also referred to as the binary system. The ditgits are represent powers of 2. Each digit can hold one of 2 possible values, zero or one. Any number can be represented in binary with a long enough string of zeroes and ones.

Binary System

Another term for the base 2 numbering system

Integers

In Mathematics, the whole numbers and the negative numbers. Decimal values and fractions are NOT integers. In computing, integers are stored with a relatively simple scheme in binary notation

Real Numbers

In Mathematics, the numbers that can be expressed as a fraction or decimal value. In computing, these are stored differently than integers. Some programs require you to specify whether you are working with real numbers or integers.

Round-Off Error

A term applied to a number of related problems common in digital computers. Any digital storage technique has limited precision. Some real numbers have infinitely precise values. Round-Off error is the generic term applied to any problem that relates to this characteristic.

Case-Sensitive

In most text recognition schemes, lowercase and uppercase letters have completely different values. (EG "A" is not given the same value as "a".) Some programs are designed to correct automatically for this feature, and some do not. This property is called "case-sensitivity" DOS is a non-case-sensitive operating system, meaning that the command "Foo" could be entered in as "foo", "Foo","fOO", or"fOo", and the command would work the same. Unix is a case-sensitive operating system, meaning that if the command were called "foo", only "foo" would work. "Foo", "fOO", and all the other variations would not. At this point, just be aware what case-sensitivity is, so you will recognize it when you see it.

Memory

A bank of switches designed to hold information. Memory does nothing but hold stuff.

Address

Each little piece of memory has a numerical address that lets the computer find and put stuff there. You generally don't have to deal with these addresses directly as the user.

Register

A number of special places in the processor that allow the computer to manipulate information. Information is brought to a register, examined, maybe changed, and maybe sent back to memory. (Depending on what program the computer is running.)

Program

A list of instructions for the computer to follow. In it's deepest level, the computer only has a few built-in instructions it can follow.

machine language

The small number of built-in instructions that are designed as a part of a computer chip. Machine language programming is very tedious and difficult.