Western Latin character sets (computing)

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Several binary representations of character sets for common Western European languages are compared in this article. These encodings were designed for representation of Italian, Spanish, Portuguese, French, German, Dutch, English, Danish, Swedish, Norwegian, and Icelandic, which use the Latin alphabet, a few additional letters and ones with precomposed diacritics, some punctuation, and various symbols (including some Greek letters). Although they're called "Western European" many of these languages are spoken all over the world. Also, these character sets happen to support many other languages such as Malay, Swahili, or Classical Latin.

Summary[edit]

The ISO-8859 series of 8-bit character sets encodes all Latin character sets used in Europe, albeit that the same code points have multiple uses that caused some difficulty. The arrival of Unicode, with a unique code point for every glyph, resolved these issues.

  • ISO/IEC 8859-1 or Latin-1 is the most used and also defines the first 256 codes in Unicode
  • ISO/IEC 8859-15 modifies ISO-8859-1 to support Finnish and French and add the euro sign.
  • In terms of printable characters Windows-1252 has everything ISO-8859-1 and ISO-8859-15 have and more.
  • IBM CP437, being intended for English only, has very little in the way of accented letters but has far more graphics characters than the others and also some Greek characters that are useful as technical symbols.
  • IBM CP850 has all the printable characters that ISO-8859-1 has (albeit arranged differently) and still manages to have enough graphics characters to build a usable text-mode user interface.
  • IBM CP858 differs from CP850 only by one character — a dotless i (ı), rarely used outside Turkey, was replaced by euro currency sign (€).
  • IBM code pages 037, 500, and 1047 are EBCDIC encodings that include all of the ISO-8859-1 characters.
  • The Mac OS Roman character set (often referred to as MacRoman and known by the IANA as simply MACINTOSH) has most, but not all, of the same characters as ISO-8859-1 but in a very different arrangement; and it also adds many technical and mathematical characters and more diacritics. Older Macintosh web browsers were known to munge the few characters that were in ISO-8859-1 but not their native Macintosh character set when editing text from Web sites. Conversely, in Web material prepared on an older Macintosh, many characters were displayed incorrectly when read by other operating systems.
  • The euro sign post-dates these (ISO-8859) specifications: conflicting ways to retrofit it led to significant difficulty until Unicode became more generally adopted.

Notes[edit]

  • The mappings for the IBM code pages are from the Unicode site supplied by Microsoft. Refer to the Unicode Consortium's document on the differences between IBM's and Microsoft's mappings for these code pages.
  • The old PC code pages actually defined printable characters for the control code ranges. While these could not be used when printing text through DOS, as they would be trapped before reaching the screen, they could be used by applications that used screen memory directly.
  • Position F0HEX was used in the Macintosh character sets for the Apple logo. The Apple logo was not accepted into Unicode due to its trademarked nature, and so Apple mapped it to a code point (U+F8FF) in the private use area. Therefore it may not display correctly in the table.
  • In Windows-1252, positions 81, 8D, 8F, 90, and 9D are unused according to the mapping tables on the Unicode site. However the conversion routines in Windows seem to convert them to the C1 control codes that are at those positions in ISO-8859-1.
  • It is common that web page tools for Windows use Windows-1252 but label the web page as using ISO-8859-1. The effect is that many non-Windows systems will not display the extra characters of Windows-1252, like € and the special quotation marks correctly. This is addressed in HTML 5, which mandates that pages labeled as ISO-8859-1 must be interpreted as Windows-1252.

History[edit]

The earlier seven-bit U.S. ASCII encoding has characters sufficient to properly represent only US-English, Latin, and Swahili. It is missing some letters and letter-diacritic combinations used in other Latin-alphabet languages. However, since there was no other choice on most U.S.-supplied computer platforms, ASCII was unavoidable in most of the non-English-speaking world (seven-bit encoding was necessitated by the limitations of early computing networks). There was the ISO 646 group of encodings which replaced some of the symbols in ASCII with local characters, but space was very limited, and some of the symbols replaced were quite common in things like programming languages.

Although seven-bit communication was the norm, most computers internally used eight-bit bytes, and they mostly put some form of characters in the 128 higher byte positions. In the early days most of these were system specific, but gradually a few standards were settled on.

In recent years, as storage and memory costs fall, the issues associated with multiple meanings of a given eight-bit code (there are seven ISO-Latin code sets alone) have ceased to be justified. All major operating systems have moved to Unicode as their main internal representation. However Windows does not support Unicode using their 8-bit character interfaces (by supporting UTF-8), so many applications continue to be restricted to these legacy character sets.

The euro sign[edit]

The coming of the euro and its euro sign introduced significant pressure to support the euro sign (€), and most 8-bit character sets had to be adapted in some way.

  • Apple with MacRoman and Sun Microsystems with Solaris OS simply replaced the generic currency sign (¤). This caused significant difficulty because organisations had found other uses for it, such as the company logo.
  • ISO introduced a further variant of ISO 8859, ISO 8859-15, which replaced the generic currency sign with the euro sign as well as making some other replacements of symbols with letters with diacritics.
  • Windows-1252 simply placed the euro sign in a gap (position 80hex) in the existing C1 control codes.

All of these issues have been resolved as operating systems have been upgraded to support Unicode as standard, which encodes the euro sign at U+20AC (decimal 8364).

Comparison table[edit]

Code points U+0000 to U+007F are not shown in this table currently, as they are directly mapped in all character sets listed here. The ASCII coding standard defines the original specification for the mapping of the first 0-127 characters.

The table is arranged by Unicode code point. Character sets are referred to here by their IANA names in upper case.

Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
NBSP U+00A0 A0 A0 A0 FF FF CA
¡ U+00A1 A1 A1 A1 AD AD C1
¢ U+00A2 A2 A2 A2 9B BD A2
£ U+00A3 A3 A3 A3 9C 9C A3
¤ U+00A4 A4   A4   CF  
¥ U+00A5 A5 A5 A5 9D BE B4
¦ U+00A6 A6   A6   DD  
§ U+00A7 A7 A7 A7   F5 A4
¨ U+00A8 A8   A8   F9 AC
© U+00A9 A9 A9 A9   B8 A9
ª U+00AA AA AA AA A6 A6 BB
« U+00AB AB AB AB AE AE C7
¬ U+00AC AC AC AC AA AA C2
SHY U+00AD AD AD AD   F0  
® U+00AE AE AE AE   A9 A8
¯ U+00AF AF AF AF   EE F8
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
° U+00B0 B0 B0 B0 F8 F8 A1
± U+00B1 B1 B1 B1 F1 F1 B1
² U+00B2 B2 B2 B2 FD FD  
³ U+00B3 B3 B3 B3   FC  
´ U+00B4 B4   B4   EF AB
µ U+00B5 B5 B5 B5 E6 E6 B5
U+00B6 B6 B6 B6   F4 A6
· U+00B7 B7 B7 B7 FA FA E1
¸ U+00B8 B8   B8   F7 FC
¹ U+00B9 B9 B9 B9   FB  
º U+00BA BA BA BA A7 A7 BC
» U+00BB BB BB BB AF AF C8
¼ U+00BC BC   BC AC AC  
½ U+00BD BD   BD AB AB  
¾ U+00BE BE   BE   F3  
¿ U+00BF BF BF BF A8 A8 C0
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
À U+00C0 C0 C0 C0   B7 CB
Á U+00C1 C1 C1 C1   B5 E7
 U+00C2 C2 C2 C2   B6 E5
à U+00C3 C3 C3 C3   C7 CC
Ä U+00C4 C4 C4 C4 8E 8E 80
Å U+00C5 C5 C5 C5 8F 8F 81
Æ U+00C6 C6 C6 C6 92 92 AE
Ç U+00C7 C7 C7 C7 80 80 82
È U+00C8 C8 C8 C8   D4 E9
É U+00C9 C9 C9 C9 90 90 83
Ê U+00CA CA CA CA   D2 E6
Ë U+00CB CB CB CB   D3 E8
Ì U+00CC CC CC CC   DE ED
Í U+00CD CD CD CD   D6 EA
Î U+00CE CE CE CE   D7 EB
Ï U+00CF CF CF CF   D8 EC
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
Ð U+00D0 D0 D0 D0   D1  
Ñ U+00D1 D1 D1 D1 A5 A5 84
Ò U+00D2 D2 D2 D2   E3 F1
Ó U+00D3 D3 D3 D3   E0 EE
Ô U+00D4 D4 D4 D4   E2 EF
Õ U+00D5 D5 D5 D5   E5 CD
Ö U+00D6 D6 D6 D6 99 99 85
× U+00D7 D7 D7 D7   9E  
Ø U+00D8 D8 D8 D8   9D AF
Ù U+00D9 D9 D9 D9   EB F4
Ú U+00DA DA DA DA   E9 F2
Û U+00DB DB DB DB   EA F3
Ü U+00DC DC DC DC 9A 9A 86
Ý U+00DD DD DD DD   ED  
Þ U+00DE DE DE DE   E8  
ß U+00DF DF DF DF E1 E1 A7
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
à U+00E0 E0 E0 E0 85 85 88
á U+00E1 E1 E1 E1 A0 A0 87
â U+00E2 E2 E2 E2 83 83 89
ã U+00E3 E3 E3 E3   C6 8B
ä U+00E4 E4 E4 E4 84 84 8A
å U+00E5 E5 E5 E5 86 86 8C
æ U+00E6 E6 E6 E6 91 91 BE
ç U+00E7 E7 E7 E7 87 87 8D
è U+00E8 E8 E8 E8 8A 8A 8F
é U+00E9 E9 E9 E9 82 82 8E
ê U+00EA EA EA EA 88 88 90
ë U+00EB EB EB EB 89 89 91
ì U+00EC EC EC EC 8D 8D 93
í U+00ED ED ED ED A1 A1 92
î U+00EE EE EE EE 8C 8C 94
ï U+00EF EF EF EF 8B 8B 95
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
ð U+00F0 F0 F0 F0   D0  
ñ U+00F1 F1 F1 F1 A4 A4 96
ò U+00F2 F2 F2 F2 95 95 98
ó U+00F3 F3 F3 F3 A2 A2 97
ô U+00F4 F4 F4 F4 93 93 99
õ U+00F5 F5 F5 F5   E4 9B
ö U+00F6 F6 F6 F6 94 94 9A
÷ U+00F7 F7 F7 F7 F6 F6 D6
ø U+00F8 F8 F8 F8   9B BF
ù U+00F9 F9 F9 F9 97 97 9D
ú U+00FA FA FA FA A3 A3 9C
û U+00FB FB FB FB 96 96 9E
ü U+00FC FC FC FC 81 81 9F
ý U+00FD FD FD FD   EC  
þ U+00FE FE FE FE   E7  
ÿ U+00FF FF FF FF 98 98 D8
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
ı U+0131         D5 F5
Œ U+0152   BC 8C     CE
œ U+0153   BD 9C     CF
Š U+0160   A6 8A      
š U+0161   A8 9A      
Ÿ U+0178   BE 9F     D9
Ž U+017D   B4 8E      
ž U+017E   B8 9E      
ƒ U+0192     83 9F 9F C4
ˆ U+02C6     88     F6
ˇ U+02C7           FF
˘ U+02D8           F9
˙ U+02D9           FA
˚ U+02DA           FB
˛ U+02DB           FE
˜ U+02DC     98     F7
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
˝ U+02DD           FD
Γ U+0393       E2    
Θ U+0398       E9    
Σ U+03A3       E4    
Φ U+03A6       E8    
Ω U+03A9       EA   BD
α U+03B1       E0    
δ U+03B4       EB    
ε U+03B5       EE    
π U+03C0       E3   B9
σ U+03C3       E5    
τ U+03C4       E7    
φ U+03C6       ED    
U+2013     96     D0
U+2014     97     D1
U+2017         F2  
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
U+2018     91     D4
U+2019     92     D5
U+201A     82     E2
U+201C     93     D2
U+201D     94     D3
U+201E     84     E3
U+2020     86     A0
U+2021     87     E0
U+2022     95     A5
U+2026     85     C9
U+2030     89     E4
U+2039     8B     DC
U+203A     9B     DD
U+2044           DA
U+207F       FC    
U+20A7       9E    
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
U+20AC   A4 80     DB
U+2122     99     AA
U+2202           B6
U+2206           C6
U+220F           B8
U+2211           B7
U+2219       F9    
U+221A       FB   C3
U+221E       EC   B0
U+2229       EF    
U+222B           BA
U+2248       F7   C5
U+2260           AD
U+2261       F0    
U+2264       F3   B2
U+2265       F2   B3
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
U+2310       A9    
U+2320       F4    
U+2321       F5    
U+2500       C4 C4  
U+2502       B3 B3  
U+250C       DA DA  
U+2510       BF BF  
U+2514       C0 C0  
U+2518       D9 D9  
U+251C       C3 C3  
U+2524       B4 B4  
U+252C       C2 C2  
U+2534       C1 C1  
U+253C       C5 C5  
U+2550       CD CD  
U+2551       BA BA  
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
U+2552       D5    
U+2553       D6    
U+2554       C9 C9  
U+2555       B8    
U+2556       B7    
U+2557       BB BB  
U+2558       D4    
U+2559       D3    
U+255A       C8 C8  
U+255B       BE    
U+255C       BD    
U+255D       BC BC  
U+255E       C6    
U+255F       C7    
U+2560       CC CC  
U+2561       B5    
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
U+2562       B6    
U+2563       B9 B9  
U+2564       D1    
U+2565       D2    
U+2566       CB CB  
U+2567       CF    
U+2568       D0    
U+2569       CA CA  
U+256A       D8    
U+256B       D7    
U+256C       CE CE  
U+2580       DF DF  
U+2584       DC DC  
U+2588       DB DB  
U+258C       DD    
U+2590       DE    
Character Code point ISO-8859-1 ISO-8859-15 WINDOWS-1252 IBM437 IBM850 MACINTOSH
U+2591       B0 B0  
U+2592       B1 B1  
U+2593       B2 B2  
U+25A0       FE FE  
U+25CA           D7
U+FB01           DE
U+FB02           DF

In addition, Macintosh assigns the Apple logo (Mac OS Roman: F0) to U+F8FF in the Private Use Area.