Unicode

Normal 8-bit coding provides 256 characters in a standard character set, which is insufficient for all the special symbols, punctuation and accented characters used in various languages. And it’s certainly inadequate for the vast range of symbols used in pictographic languages such as Chinese or Japanese.

Unicode, also known as ISO 10646-M, uses 16-bit codes to define up to 65,536 characters. These are grouped as shown in the following table:-

Although all of these Unicode codes are fully standardised, many applications or computer operating systems are limited to showing only some of the characters.

Further details regarding some these groups appear in the following sections.

• Click here to see a more extensive list of the Unicode groups.

• Click here to see a full textual description of all Unicode characters.

Codes 0 to 255: Alphabetic Characters and Punctuation

The characters generated by these codes are identical to those defined by the ASCII standard and the ISO 8859-1 standard, the latter also known as Latin-1. This makes it easy to convert material that’s coded using a western-based character set, often known as Roman, into Unicode form.

The ISO 8859-1 character set is as follows:-

The codes from 128 to 159 should be avoided, as these can be used for non-standard characters.

Codes 256 to 912: Special Characters and Accents

This area is used for less common accented characters, many of which appear with an accent separate to the letter itself, as shown below. Characters that can’t be displayed by your browser appear as a ? (query) or as a keyboard button symbol.

Of these, and other codes in this group, the following are the most useful:-

The remaining codes in this block are assigned to other obscure characters.

Codes 913 to 982: Greek characters

These characters are often used in maths and other applications. For simplicity, unassigned codes have been omitted from the following table.

Codes 8192 to 12287: Special Characters and Punctuation

These codes are used for rather less common characters and punctuation. The following table only shows the more usual characters, with numerous rows omitted for clarity. Some codes don’t appear to create any visible character but are in fact used for a range of different types of spaces. Those characters that can’t be displayed by your browser are indicated by a ? or by a keyboard button symbol.

Of these, the following are commonly used:-

©Ray White 2004.