Character Sets (Language Scripts)

You may see the following tags in web pages:
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
Other common charset Values:
  us-ascii & windows-1252 (IBM Extended Character Set - ECS)
  These are basically the same. Other character sets are listed below.
 The first 128 characters are control characters and 
 the standard letters, numbers, and special chaaracters (punctuation, +, /, =, ...).
 The extended characters (128-256)(80-FF octal) include multinational characters
 and things like cent "¢", pound "£", copyright "©".
 The 8-bit character file here has the printable characters from 32-255.
The extended characters are standardized for web pages, but when viewed in
native text editors may appear differently in different operating systems.
e.g. Windows, Macintosh OS, and UNIX.
Other HTML Coding for Character Sets

HTML also uses something called character entity references to specify characters 
(e.g.  &copy; or &#169; for obtaining the copyright sign ©)
The codes (e.g. 169) are the same as the Extended ANSI character codes.

Character Entity Ref. codes also exist for other characters such as greek letters
 and mathmatical symols.

More characters are available with unicode (UTF-16) character encoding like
U+2646 coded as &#x2646; for ♆, the symbol for Neptune.

See The Problem with Em 'n Em and other special characters for a good explanation.
Notation
Notation for Space
Octal Decimal Hex
\040     32  \x20
URL's use Hex characters e.g. %20  for space.
Character entity references use the decimal char e.g. &#32;

International Standards Orginization (ISO) 8859 and Microsoft Codepages are other common standards.

BOLD - Prefered MIME Name
<
Table at Encoding.CodePage Property msdn.microsoft.com
Name      CodePage  BodyName    HeaderName   WebName    Encoding.EncodingName
shift_jis     932  iso-2022-jp  iso-2022-jp  shift_jis    Japanese (Shift-JIS)
windows-1250 1250  iso-8859-2   windows-1250 windows-1250 Central European1 Latin-2
windows-1251 1251  koi8-r       windows-1251 windows-1251 Cyrillic 
Windows-1252 1252  iso-8859-1   Windows-1252 Windows-1252 Western European Latin-1
windows-1253 1253  iso-8859-7   windows-1253 windows-1253 Greek 
windows-1254 1254  iso-8859-9   windows-1254 windows-1254 Turkish 
csISO2022JP  50221 iso-2022-jp  iso-2022-jp  csISO2022JP  Japanese (JIS-Allow 1 byte Kana)
iso-2022-kr  50225 iso-2022-kr  euc-kr       iso-2022-kr  Korean (ISO)
1. Latin-2 Central or East  European (Czech, Hungarian, Polish and Slovak)

B>US-ASCII (U.S. national variant of ISO/IEC 646. Formally, the U.S. standard
                                  ANSI X3.4.)
    ISO             Windows
ISO-8859-1 - 1252 - Latin-1 Westerm European (Default)ANSI 
ISO-8859-2 - 1250 - Latin-2 East European (Czech, Hungarian, Polish and Slovak)
ISO-8859-3 - Latin-3 South European
ISO-8859-4 - 1257 - Latin-4 North European (Baltic)
ISO-8859-10 - Latin-6 Nordic replaces latin-4 (Sámi, Inuit, Icelandic) 
ISO-8859-5 - 1251 - Cyrillic (Azerbaijani, Bulgarian, Buryat, Byelorussian, Karakalpak,
             Kazakh, Khalkha, Kirghiz, Macedonian, Moldavian, Russian, Serbian,
             Tajik, Turkmen, Ukrainian and Uzbek languages)
ISO-8859-6 - 1256 - Arabic (Arabic, Farsi [Iran], Jawi, Kurdish, Pashto [Afghanistan],
                   Persian, Sindhi and Urdu [Pakistan], Panjabi)
ISO-8859-7 - 1253 - Greek
ISO-8859-8 - 1255 - Hebrew
ISO-8859-9 - 1254 - Latin-5 Turkish 
                    1258 - Viet Nam 
ISO-8859-11 - 874 - Thai 
ISO-2022-KR - 949 - Korean Extended Wansung 
936 - PRC GBK (XGB) 
950 - Chinese (Taiwan, Hong Kong) 

 2 Byte (16 bit) codes
 UTF-8  - ISO-10646  Unicode
 Big5   - Chinese Traditional (Taiwan, HongKong)
 EUC-TW - Chinese Traditional
 GB2312  - Chinese Simplified (China mainland, Singapore and Malaysia)
 GB18030 is the registered Internet name for the official character set of
                the People's Republic of China (PRC) superseding GB 2312.
 GB - (GuoBiao) Chinese Simplified
 GBK - Chinese Simplified
 HZ - Chinese Simplified
 ISO-2022-GB - an emerging new international Internet standard for encoding Chinese text

 EUC-JP  Japanese
 EUC-JIS  Japanese
 Shift_JIS  Japanese
 ISO-2022-JP  Japanese
 ISO-2022-JP2  Japanese
 KSC5601 - Korean
 EUC-KR - Korean
 KSC5601
 KO18-R - Cyrillic
 KO18-U - Cyrillic
 Devanagari (Bhojpuri, Bihari, Hindi, Kashmiri, Konkani, Marathi, Nepali and Sanskrit.
            It is also used for writing Panjabi by Indians who are not Sikhs)
Gujarati  (Indian State of Gujarat)
Gurmukhi (Panjabi[Pakstan and  India]
           Panjabi can also be written with Devanagari and Arabic)
Bengali  Bengali [Bangladesh]

Thai
Vietnamese


 (Character sets recognized in Netscape 1.1 were us-ascii, iso-8859-1, iso-2022-jp,
 x-sjis, x-euc-jp, x-mac-roman)
 Central European

There 8, 16 and 32 bit Unicode transformation formats (UTF)

• UTF-7 - For 7-bit environments
• UTF-8 is the byte-oriented encoding form of Unicode. It uses anywhere between one and four bytes to encode a character.
• UTF-16 Uses two bytes for the characters inside the basic multilingual plane (BMP). UTF-16 is popular because many APIs date to the time when Unicode was 16-bit fixed width. Characters outside the BMP may require surrogate pairs in UTF-16.
• UTF-32 Uses four bytes for all characters, so you don't have to worry about characters outside the BMP.
• UTF-EBCDIC is a character encoding used to represent Unicode characters. It is meant to be EBCDIC-friendly, so that legacy EBCDIC applications on mainframes may process the characters without much difficulty.
• GB18030 (Simplified Chinese) can be considered a Unicode Transformation Format (i.e. an encoding of all Unicode code points) that maintains compatibility with a legacy character set. In other words, it is a Chinese equivalent of UTF-8

UTF-16 and UTF-32 are not byte oriented and so a byte order must be selected when transmitting them over a byte oriented network or storing them in a byte oriented file.

Some systems store data with most significant byte (MSB) first (big-endian) and others with it last (little-endian). A byte order mark (BOM) consists of the character code U+FEFF at the beginning of a data stream, where it can be used as a signature defining the byte order and encoding form, primarily of unmarked plaintext files.

See: unicode.org, Allan Wood's Unicode Page Reference.com (Table of Unicode characters, 128 to 999 Table of Unicode characters from 1 to 65535 at unicode.coeurlumiere.com

Some of the Languages in the Unicode Character Database (UCD) . See a larger list at Alan Wood's Unicode and Multilingual Support in HTML

Armenian Bengali Block Elements Bopomofo Bopomofo Extended Box Drawing Braille Patterns Canadian Aboriginal Syllabics Cherokee CJK Chinese/Japanese/Korean Dingbats Ethiopic Georgian

Hangul Compatibility Jamo Hangul Jamo Hangul Syllables Hebrew High Surrogates Hiragana Ideographic Description Characters IPA Extensions Kanbun KangXi Radicals Kannada Katakana

Khmer Lao Malayalam Mathematical Operators Miscellaneous Symbols Miscellaneous Technical Mongolian Myanmar Number Forms Ogham Oriya

Runic Sinhala Syriac Tamil Telugu Thaana Thai Tibetan "Unified Canadian Aboriginal Syllabics" Yi Radicals Yi Syllables

CJK Chinese/Japanese/Korean come in several Unicode subsets: CJK compatibility, CJK Unified Ideographs (Extension A & B), CJK Compatibility Ideographs, CJK compatibility Forms, CJK Symbols and Punctuation, CJK Radicals Supplement, CJK Compatibility Ideographs Supplement, CJK Miscellaneous

ISO/ANSI vs characters

Microsoft

<META HTTP-EQUIV="Content-Language" CONTENT="zh">
<HTML LANG="fr">
<BLOCKQUOTE LANG="fr">
<P LANG="fr">

Common values: (See: ISO639A List)
ar - Arabic, de - German, en - english, es - Spanish, fr - french, ga - Irish,
gu - Gujarati, he - Hebrew, hi - Hindi, it - Italian, ja - japanese, ko - korean,
pa - Punjabi, yi - Yiddish, zh - Chinese

They may also contain sub-tags e.g.:
fr-CA - French Canadian
ar-EG - Egyptian Arabic
en-US - American English
zh-TW - Taiwanese Chinese
zh-Hant - Traditional Chinese
zh-Hans - Simplified Chinese

Fonts

* - Standard on Macintosh and UNIX, † - Standard on Windows
Chinese Traditional: MingLiU (IE5), PMingLiU (office 2000)
Chinese Simplified: MS Song  (IE5), MS Hei  (IE5), SimSun (Office 2000)
Japanese:  MS Gothic, MS Mincho
Korean: Gulimche
Web HebrewAD and Web Hebrew Monospace
Others: (See Alan Wood's list)
FZNew XiuLi-Z11

Terms

ANSI - American National Standards Institute
Big5 - Character Set used for Traditional Chinese Characters
CJK - Chinese/Japanese/Korean
ECS - IBM Extended Character Set
EUC - Extended UNIX Code
GB (GuoBiao) - Character Set used for Simplified Chinese Characters
ISO - International Standards Organization
UCD - Unicode Character Database
UTC - Unicode Technical Committee
UTF - Unicode transformation format