●Major properties of digital data
Item
Explanation
Data transmission
Transmittable to distant locations
Data sharing
Can be jointly used over a network
Data image
processing
Can be editted and processed using functions such as expansion, shrinkage, and trimming
Data image quality
Does not deteriorate
Data compression
Executable
Data searching
Executable
Data copying
Executable
Character representation
3
Internally, a computer treats characters as binary numbers. The binary code
to which all characters are assigned is known as a “character code.”
Type
Reference
ASCII
The character code standardized by ANSI (American National Standards Institute). A 7-bit code system which expresses alphanumeric
characters and symbols. By adding a parity bit, it can be represented as one byte.
JIS
The character code standardized by JIS (Japanese Industrial Standards). It consists of a 1-Byte code system, which expresses alphanumeric characters and symbols, and also a 2-Byte code system,
which represents Chinese and Japanese characters.
Shift JIS
A character code standardized by Microsoft. A 2-Byte code system,
which combines the JIS 2-Byte code with the ASCII 1-Byte code. It
is used on a wide range of computers via Windows, Mac OS, and
other operating systems.
EUC
A character code standardized by AT&T. Short for “Extended Unix
Code,” this 2-Byte code system allows for Chinese characters to be
used via the Unix operating system.
EBCDIC
An 8-bit character code standardized by IBM in the United States. It
has mostly been adopted for large, multi-purpose computers.
Unicode
A character code standardized by ISO (International Organization
for Standardization) and IEC (International Electrotechnical Commission). A 2-Byte code system which incorporates characters used
throughout the entire world.
Parity bit
A “parity bit” is a bit which allows for
character code errors to be inspected.
Reference
EUC
Abbreviation for “Extended Unix Code.”
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Explanation