2. Definitions and abbreviations

ASCII (American National Standard Code for Information Interchange).

American national 7-bit character code standard for use in information interchange, data processing and communications systems. The ASCII code table includes control characters and graphic characters. The left part of the Estonian basic code table coincides with the ASCII code table.

ISO

International Organization for Standardization

IEC

International Electrotechnical Commission

MES

Multilingual European Subset. MES-1, MES-2 and MES-3A are defined as ISO/IEC 10646 collections.

ISO/IEC 10646, Unicode

International standard for representation, transmission, interchange, processing, storage, input and representation of the written form of the languages of the world as well as additional symbols. ISO/IEC 10646 and Unicode are used as synonyms in this standard.

UCS

Universal Multiple-Octet Coded Character Set as specified in ISO/IEC 10646.

Control function, control character.

A character that acts as a command for an activity (line feed, end of message, etc) and that does not possess a self-dependent graphic image. In the present standard, control characters are not included. Their use must be in accordance with international standards, which have the columns 0, 1 (or C0 range) and 8, 9 (C1 range) reserved for control characters.

Graphic character (kirjamärk, graafiline märk).

Unlike a control character, a graphic character has a visual image, it can be written by hand, printed or displayed on a screen.

Character (märk).

A member of a set of elements used for the organization, control, or representation of data.

Character set, character repertoire (märgistik, märgivalik).

A complete set of characters. Any character set can be coded in several ways.

Coded character set (kodeeritud märgistik).

A set of unambiguous rules that establishes a character set and the relationship between the characters of the set and their coded representation.

Code table, code page (kooditabel, koodilehekülg).

Representation of a coded character set in the form of a table. A single byte code table consists of 256 positions: 16 rows and 16 columns. The rows and columns are numbered with hexadecimal digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F. In the hexadecimal code of a character xy the digit x represents the column and y the row.

Script (kirjasüsteem e kiri).

A set of graphic characters used for the written form of one or more languages. Estonian uses Latin script. Other scripts used in Europe include Greek, Hebrew and Cyrillic script.

Letter (täht).

A graphic character that is in the alphabet of a natural language.

Diacritical mark (diakriitiline märk e diakriitik).

An additional sign in the composition of a character, e.g. diaeresis.

Ligature.

A compound of two characters, e.g. "OE".

Byte, octet (bait, oktett).

An ordered sequence consisting of 8 bits (binary digits) considered as a unit. Instead of a 8-digit binary number, the corresponding decimal or hexadecimal numbers can be used. For instance, the bit sequence "11011100" can be written as the decimal number "220" or hexadecimal number "DC".

EBCDIC, Extended Binary Coded Decimal Interchange Code.

A code table family used in IBM mainframes. The Estonian EBCDIC code table is based on the IBM CP 278 table.

Latin-1, Latin alphabet #1.

A character set consisting of 191 characters used in West Europe, North, Middle and South America. Latin-1 is formed as the standard ISO 8859-1.

Latin-9, Latin alphabet #9.

A character set based on Latin-1 and consisting of 191 characters where seven new characters previously omitted in Latin-1 are inserted the code range A0-BF. Latin-9 is formed as the standard ISO 8859-15 and used as the basic code table for Estonian.

Language layer (on a keyboard).

A keyboard may possess several language layers (e.g., Estonian and Russian layers). Every language layer has up to three cases (lower case, upper case, supplementary case).

QWERTY keyboard.

Keyboard arrangement, containing in the second row (row D) from left to right the letters Q, W, E, R, T, Y, U, I, O, P. This keyboard dominates in cultures using the Latin alphabet (with exception of the French culture). The Estonian keyboard presented in this standard is a modification of the QWERTY keyboard. The AZERTY keyboard is used in French cultural environment, the QWERTZ keyboard has been in use in the German culture.

Case, keyboard level.

Pressing any key of the keyboard inside a language layer, up to three different characters can be generated depending on the keyboard being in the lower (level 1), upper (level 2) or supplementary (level 3) case.

Nonescaping key, nonspacing key, dead key.

A key on the keyboard, with does not change the position of the cursor. A nonescaping key can be used to generate characters with diacritics.

Capslock, capitals lock.

A function of a keyboard key, that switches the keyboard driver to the capitals case, but does not influence keys with digits and other characters. The capitals lock is a case key: by pressing it, the corresponding function is switched on or off.

POSIX, Portable Operating Systems Interface.

A standard mobile operating system and its environment. POSIX may be looked at as a standardized UNIX. This standard defines an Estonian locale compliant to POSIX.

Locale.

The definition of the environment of a user that depends on language and cultural conventions. It is made up from one or more categories. Each category is identified by its name and controls specific aspects of the behaviour of components of the system. ISO/IEC 14652 defines several new categories in addition to the categories defined in POSIX, e.g. for representation of postal addresses or paper sizes.

FDCC-set (set of Formal Definitions of Cultural Conventions).

The definition of the subset of a user's information technology environment that depends on language and cultural conventions. The FDCC-set is a superset of the "locale" term in C and POSIX.