Unicode Explained

Good Old ASCII

ASCII is still the set of characters that work safely in most text applications and on the

Internet. Almost all programming languages, command languages, markup languages,

Internet protocol headers, and many other notation systems still exclusively use ASCII

in their basic syntax. They may allow other characters in contexts like quoted strings,

but the commands, reserved words, and operators are written using good old ASCII.

Moreover, most character codes currently in use can be regarded as extensions of ASCII:

they preserve the meaning of code numbers 0 through 127 and add some more.

On the other hand, ASCII has a very small character repertoire. Historically, it was a

big improvement over even more restricted character codes, but it was created at a time

when bits were very expensive. ASCII was designed to be represented in 7 bits, and

many character positions were reserved for control codes such as linefeed (LF) and

escape (ESC). Only about a hundred character positions were assigned to printable

characters.

Moreover, since the needs of programming were more important than those of text

processing, the assignments use positions for many technical characters. Even “smart”

quotation marks were omitted; the idea was that the ASCII quotation mark, ", was to

be used as a neutral quotation mark.

American Origin

The name ASCII is originally an acronym for “American Standard Code for ...