Esperanto is written in an alphabet of twenty-eight letters. Twenty-two of these are identical in form to letters of the English alphabet (q, w, x, and y being omitted). The remaining six are accented letters, which appear as follows: ĉ, ĝ, ĥ, ĵ, ŝ (c, g, h, j, and s with circumflex), and ŭ (u with breve). The full alphabet appears as follows:-

Table of contents 1 a b c ĉ d e f g ĝ h ĥ i j ĵ k l m n o p r s ŝ t u ŭ v z 1.1 The h-system 1.2 The x-system 1.3 Use of the caret 1.4 Exceptions to the rules 1.5 Unicode 1.6 See also

a b c ĉ d e f g ĝ h ĥ i j ĵ k l m n o p r s ŝ t u ŭ v z

The alphabet is phonetic in that each letter has a consistent sound, although the mapping from phonemes to letters is not always unique because certain letters are pronounced as combinations of other letters (c = ts; ĉ = tŝ; ĝ = dĵ).

In handwritten Esperanto, the accented letters cause no problems. However, since none of them appear on standard alphanumeric keyboards, various different methods have been devised for representing them in printed and typed text using more standard characters. The original method was what is now referred to as the "h-system", but this has now largely been superseded by the so-called "x-system". With the advent of Unicode, the need for such systems is lessening.

The h-system

The original method of representing accented letters is due to the initiator of Esperanto, L. L. Zamenhof, who recommended using u in place of ŭ, and putting an h after a letter to indicate that the letter should have a circumflex. For example, the consonant ŝ is represented as sh, as in the words shi (ŝi, meaning she) and shanco (ŝanco, meaning chance).

Unfortunately this method suffers from two problems:

1. h is already a consonant in the language, so its use for another purpose would make the pronunciation and sometimes the meaning of words ambiguous.
2. Simplistic ASCII-based rules for sorting English words fail badly for sorting Esperanto ones, because lexicographically words starting with ĉ should follow words starting with c and precede words staring with d. For example ĉu should be sorted after ci lexicographically, but written in the h-system, chu would be incorrectly sorted before ci.

The x-system

The most common system for typing in Esperanto today is the "x-system", which uses x after a letter to indicate that the letter should have an accent. For example, the consonant ŝ is represented as sx, as in the words sxi (ŝi) and sxanco (ŝanco).

This method solves both of the problems inherent in the h-system:

1. x is not a consonant in the language, so its use introduces no ambiguity into the pronunciation or meaning.
2. Words starting with cx now correctly follow words starting with c. Similarly, other accented letters are sorted after their unaccented friends. The sorting only fails when a word with cz or similar is encountered, but such words are relatively uncommon.

One problem with the x-system is when it is used alongside French text, because many French words end in ux. For example, aux (aŭ in Esperanto) is a word in both languages.

Use of the caret

Another, less popular, system is the use of the caret[?] character (^) to represent the accents, either before or after the letter to be accented. For example, ŝanco becomes ^sanco or s^anco. This shares the advantage of unambiguity with the x-system, and also has the advantage that the character itself resembles a circumflex accent, so that people unfamiliar with the system are likely to grasp what is meant. However, the system has not caught on in many places.

Exceptions to the rules

Some people do not bother to mark the accent on the letter u in the x-system, because ux is almost always part of the diphthong aux (like the ow in cow, without the rounding of the lips) or eux (as in Spanish Europa), whereas the letter combinations au and eu almost never occurs. Hence, morgau ("tomorrow") instead of morgaux, Europo ("Europe") instead of Euxropo. This is more common when using other systems.

Unicode

The entire Esperanto alphabet is part of the Latin-3 and Unicode character sets, so the above systems are no longer necessary on web pages, though the x-system remains common on Usenet and in e-mail where encoding support is rare and the limited availability of keyboard configurations makes it difficult for many to comfortably type.

See also

• orthography