Diacritical Marks

(also called diacritics), various marks that are located above, below, and less frequently, on the line; used in letter types of writing for changing or specifying the value of individual signs. The following types of diacritical marks are differentiated: marks that give a letter a new value, such as Й, ë, ä, ă, Θ, ƒ and Љ in the alphabets of the peoples of the USSR based on the Russian alphabet and å, θ, ü, š, ç, ¯n, and ł in the Latin alphabet, and marks designating variants of a sound, such as è, é and ê in French, which also differentiate meaning. Some diacritical marks indicate that the letter should be read separately (for example, French ï). Prosodic diacritical marks indicate length or shortness, stress and its types, and tones (in Vietnamese and some Latin writing systems for Chinese).

Diacritical marks play a large role in certain transcription systems and in plans for international alphabets. The same diacritical marks have a different meaning in different national writing systems. There is a particularly large number of diacritical marks in the French, Portuguese, Polish, Czech, Latvian, and Lithuanian writing systems based on the Latin alphabet and in the writing systems of the peoples of the USSR based on the Russian alphabet (in which the purpose of the diacritical marks has been standardized wherever possible). Diacritical marks are also used in Arabic (to differentiate the letters shin and sin), in writing systems created on the basis of Arabic script (for example, Persian), and in the Indie system of writing (where they indicate a nasal consonant and also differentiate the length and shortness of [u] and [i]).

Some scholars also treat as diacritical marks the system of vocalization in the Semitic types of writing (for example, in Arabic and Hebraic writing), in which vowel sounds are designated by dots or dashes under consonants.