How to read charts

The charts list characters in assending order according to their collation (or locale) rules.

The color and the border of the cell indicates the strength of the difference between that character and the previous character in the chart, as follows.

	Simple		Expansion		Conraction		Conraction with expansion		Ignorable
Primary difference	A 41 0041		æ E6 00E6		CH 4348 00430048		ggy 676779 006700670079		ctrl 00 0000
Secondary difference	Á C1 00C1		ü FC 00FC		AA 4141 00410041				¤ A4 00A4
Tertiary difference	á E1 00E1		Æ C6 00C6		ch 6368 00630068		GGY 474759 004700470059		+ 2B 002B
Quarternary difference	ๅ E5 0E45								ctrl 0B 000B
Quinary difference	W 57 0057								¯ AF 00AF
Senary difference, or equal	w 77 0077		ä E4 00E4						‚ 82 201A

Each cell consists of:

• a character (of multiple characters in case of contractions)
• its code according to the character set of the chart,
• as well as its Unicode code point.

Cells can represent character-to-weight mappings of the following types:

• Ignorable - a character doesn't have weights on the primary level (but may have weights on the secondary or the tertiary, or the higher levels). Often, punctuation characters are ignorable.

  For example, Windows locales and Fedora Core locales ignore on the first level the "U+002D HYPHEN-MINUS" (and some other punctuation characters), which helps to sort in a "culturally correct" way, when "co-operation" is sorted near "cooperation": both after "convexity" and before "copper". I.e. the hyphen character is ignored on the first pass of comparison, it is checked later, when a sorting program needs to detect mutual order of the words "cooperation" and "co-operation", and the former goes first.

• Simple - a character has a single weight on the primary level.

  Most letter and digit characters have simple weight mappings.

• Expansion - a character has multiple weights on the primary level. For example in German, the letter "ß" (U+00DF SHARP S) produces two weights and is sorted near "ss" (LATIN SMALL LETTER S followed by another LATIN SMALL LETTER S).
• Contraction - when multiple characters act as a single letter. For example in Czech, the combination of two characters "CH" is considered as a single letter, which is sorted after "H" and before "I".

  Firebird calls this phenomena as "compression". We'll use the word "contraction" which is a more traditional term.

• Contraction with expansion - when a special sequence of multiple characters produce multiple weights. Examples of such mapping between characters and weights can be found in Hungarian. The combination of two characters "CS" is a single letter, which is sorted after "C" and before "D", and which gives a single weight in the primary level. Thus "CS" itself is an example of a contraction, described in the previous paragraph. However, when letter "CS" is followed by another letter "CS" - they can be written together using a short form, as "CCS", which is collated as CS+CS (rather than C+CS). These short Hungarian forms are called as simplified geminate of multigraphs, and they are examples of contractions with expansion. Thus, "CCS" is a sequence of three characters which give two weights on the primary level.