Ch1_digital

Kilobit (Kbit or Kb)

0

Megabit (Mb or Mbit)

1,048,576 bits.

Unicode

A 16-bit character-representation code that can represent more than 65,000 characters.

ASCII (American Standard Code for Information Interchange)

A code that represents characters as a series of 1s and 0s. Most computers use ASCII code to represent text, making it possible to transfer data between computers. d

Lossless compression

A compression technique that is able to reconstitute all of the data in the original file; hence, lossless means that this compression technique does not lose data.

Binary number system

A method for representing numbers using only two digits: 0 and 1. Contrast to the decimal number system, which uses ten digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9.

File

A named collection of data (such as a computer program, document, or graphic) that exists on a storage medium, such as a hard disk or CD.

Delimiter

A special character used to separate commands or formatting characters from the rest of the text in a file.

UTF-8

A variable-length coding scheme that uses seven bits for common ASCII characters, but uses 16-bit Unicode as necessary.

Byte

An 8-bit unit of data that represents a single character.

Lossy compression

Any data compression technique in which some of the data is sacrificed to obtain more compression.

Gigabit (Gb or Gbit)

Approximately 1 billion bits; exactly 1,024 megabits.

Gigabyte (GB)

Approximately 1 billion bytes; exactly 1,024 megabytes (1,073,741,824 bytes).

Megabyte (MB)

Approximately 1 million bytes; exactly 1,048,576 bytes.

Kilobyte (KB)

Approximately 1,000 bytes; exactly 1,024 bytes.

Digitization

Converting non-digital information or media to a digital format through the use of a scanner, sampler, or other input device.

Data

In the context of computing and data management, refers to the symbols that a computer uses to represent facts and ideas.

Character data

Letters, symbols, or numerals that will not be used in arithmetic operations (name, Social Security number, etc.).

Numeric data

Numbers that represent quantities and can be used in arithmetic operations.

Extended ASCII

Similar to ASCII but with 8-bit character representation instead of 7-bit, allowing for an additional 128 characters.

ASCII text

Text files that contain no embedded formatting codes. d

Digital data

Text, numbers, graphics, or sound represented by discrete digits, such as 1s and 0s.

File name extension

The characters in a file name after the period, such as .exe and .txt.

File format

The method of organization used to encode and store data in a computer. Text formats include DOCX and TXT. Graphics formats include BMP, TIFF, GIF, and PNG.

Bit rate

The number of bits that are transmitted or processed per unit of time (usually per second); usually measured as bps (bits per second).

Binary

The representation of data using two states, such as off-on or 1-0.

Bit

The smallest unit of information handled by a computer. A bit is one of two values, either a 0 or a 1. Eight bits constitute a byte, which can represent a letter or a number.

Data representation

The use of electronic signals, marks, or binary digits to represent character, numeric, visual, or audio data.