Верхний и нижний регистр букв

Uppercase or lowercase

Letter case is the distinction between the letters that are in larger uppercase or capitals (or more formally majuscule) and smaller lowercase (or more formally minuscule) in the written representation of certain languages. The writing systems that distinguish between the upper and lowercase have two parallel sets of letters: each in the majuscule set has a counterpart in the minuscule set. Some counterpart letters have the same shape, and differ only in size (e. g. or ), but for others the shapes are different (e. g., or ). The two case variants are alternative representations of the same letter: they have the same name and pronunciation and are typically treated identically when sorting in alphabetical order. Letter case is generally applied in a mixed case fashion, with both upper and lowercase letters appearing in a given piece of text for legibility. The choice of case is often prescribed by the grammar of a language or by the conventions of a particular discipline. In orthography, the uppercase is primarily reserved for special purposes, such as the first letter of a sentence or of a proper noun (called capitalisation, or capitalised words), which makes the lowercase the more common variant in regular text. In some contexts, it is conventional to use one case only. For example, engineering design drawings are typically labelled entirely in uppercase letters, which are easier to distinguish individually than the lowercase when space restrictions require very small lettering. In mathematics, on the other hand, uppercase and lower case letters denote generally different mathematical objects, which may be related when the two cases of the same letter are used; for example, x may denote an element of a set X.

Majuscule ('/m//æ//dʒ//ə//s//k//juː//l/, less commonly /m//ə/'/dʒ//ʌ//s//k//juː//l/), for palaeographers, is technically any script whose letters have very few or very short ascenders and descenders, or none at all (for example, the majuscule scripts used in the Codex Vaticanus Graecus 1209, or the Book of Kells). By virtue of their visual impact, this made the term majuscule an apt descriptor for what much later came to be more commonly referred to as uppercase letters.

Minuscule refers to lower case letters. The word is often spelled miniscule, by association with the unrelated word miniature and the prefix mini That has traditionally been regarded as a spelling mistake (since minuscule is derived from the word minus are the letters with ascenders, and g, j, p, q, y are the ones with descenders. In addition, with old style numerals still used by some traditional or classical fonts, 6 and 8 make up the ascender set, and 3, 4, 5, 7 and 9 the descender set.

A minority of writing systems use two separate cases. Such writing systems are called bicameral scripts. These scripts include the Latin, Cyrillic, Greek, Coptic, Armenian, Glagolitic, Adlam, Warang Citi, Cherokee, Garay, Zaghawa, Osage, Vithkuqi, Old Hungarian, and Deseret scripts. Languages written in these scripts use letter cases as an aid to clarity. The Georgian alphabet has several variants, and there were attempts to use them as different cases, but the modern written Georgian language does not distinguish case. All other writing systems make no distinction between majuscules and minuscules a system called unicameral script or unicase. This includes most syllabic and other non alphabetic scripts. In scripts with a case distinction, lowercase is generally used for the majority of text; capitals are used for capitalisation and emphasis when bold is not available. Acronyms (and particularly initialisms) are often written in all caps, depending on various factors.

Capitalisation is the writing of a word with its first letter in uppercase and the remaining letters in lowercase. Capitalisation rules vary by language and are often quite complex, but in most modern languages that have capitalisation, the first word of every sentence is capitalised, as are all proper nouns. Capitalisation in English, in terms of the general orthographic rules independent of context (e. g. title vs. heading vs. text), is universally standardised for formal writing. Capital letters are used as the first letter of a sentence, a proper noun, or a proper adjective. The names of the days of the week and the names of the months are also capitalised, as are the first person pronoun "I" and the vocative particle "O". There are a few pairs of words of different meanings whose only difference is capitalisation of the first letter. Honorifics and personal titles showing rank or prestige are capitalised when used together with the name of the person (for example, "Mr. Smith", "Bishop Gorman", "Professor Moore") or as a direct address, but normally not when used alone and in a more general sense. It can also be seen as customary to capitalise any word in some contexts even a pronoun referring to the deity of a monotheistic religion. Other words normally start with a lower case letter. There are, however, situations where further capitalisation may be used to give added emphasis, for example in headings and publication titles (see below). In some traditional forms of poetry, capitalisation has conventionally been used as a marker to indicate the beginning of a line of verse independent of any grammatical feature. In political writing, parody and satire, the unexpected emphasis afforded by otherwise ill advised capitalisation is often used to great stylistic effect, such as in the case of George Orwell's Big Brother. Other languages vary in their use of capitals. For example, in German all nouns are capitalised (this was previously common in English as well, mainly in the 17th and 18th centuries), while in Romance and most other European languages the names of the days of the week, the names of the months, and adjectives of nationality, religion, and so on normally begin with a lower case letter. On the other hand, in some languages it is customary to capitalise formal polite pronouns, for example De, Dem (Danish), Sie, Ihnen (German), and Vd or Ud (short for usted in Spanish). Informal communication, such as texting, instant messaging or a handwritten sticky note, may not bother to follow the conventions concerning capitalisation, but that is because its users usually do not expect it to be formal. The Greek upper case letter "Σ" has two different lower case forms: "ς" in word final position and "σ" elsewhere. In a similar manner, the Latin upper case letter "S" used to have two different lower case forms: "s" in word final position and " ſ " elsewhere. The latter form, called the long s, fell out of general use before the middle of the 19th century, except for the countries that continued to use blackletter typefaces such as Fraktur. When blackletter type fell out of general use in the mid 20th century, even those countries dropped the long s.
The treatment of the Greek iota subscript with upper case letters is complicated. Unlike most languages that use Latin script and link the dotless upper case "I" with the dotted lower case "i", Turkish as well as some forms of Azeri have both a dotted and dotless I, each in both upper and lower case. Each of the two pairs ("İ/i" and "I/ı") represents a distinctive phoneme. In some languages, specific digraphs may be regarded as single letters, and in Dutch, the digraph "IJ/ij" is even capitalised with both components written in uppercase (for example, "IJsland" rather than "Ijsland"). Some English surnames such as fforbes are traditionally spelt with a digraph instead of a capital letter (at least for ff). In the Hawaiian orthography, the okina is a phonemic symbol that visually resembles a left single quotation mark. Representing the glottal stop, the okina can be characterised as either a letter or a diacritic. As a unicase letter, the okina is unaffected by capitalisation; it is the following letter that is capitalised instead. According to the Unicode standard, the okina is formally encoded as , but it is not uncommon to substitute this with a similar punctuation character, such as the left single quotation mark or an apostrophe.

In English language publications, various conventions are used for the capitalisation of words in publication titles and headlines, including chapter and section headings. The rules differ substantially between individual house styles. The convention followed by many British publishers (including scientific publishers like Nature and New Scientist, magazines like The Economist, and newspapers like The Guardian and The Times) and many U. S. newspapers is sentence style capitalisation in headlines, i. e. capitalisation follows the same rules that apply for sentences. This convention is usually called sentence case. It may also be applied to publication titles, especially in bibliographic references and library catalogues. An example of a global publisher whose English language house style prescribes sentence case titles and headings is the International Organization for Standardization (ISO). For publication titles it is, however, a common typographic practice among both British Another solution sometimes seen in Web typography is to use a serif font for "lower case ell" in otherwise sans serif material (1 l). The letter case of a prefix symbol is determined independently of the unit symbol to which it is attached. Lower case is used for all submultiple prefix symbols and the small multiple prefix symbols up to "k" (for kilo, meaning 103 = 1000 multiplier), whereas upper case is used for larger multipliers: or bumpy case. When the first letter of the first word is lowercase ("iPod", "eBay", "theQuickBrownFox "), the case is usually known as lower camel case or dromedary case (illustratively: dromedaryCase). This format has become popular in the branding of information technology products and services, with an initial "i" meaning "Internet" or "intelligent", as in iPod, or an initial "e" meaning "electronic", as in email (electronic mail) or e commerce (electronic commerce).

Punctuation is removed and spaces are replaced by single underscores. Normally the letters share the same case (e. g. "UPPER CASE EMBEDDED UNDERSCORE" or "lower case embedded underscore") but the case can be mixed, as in OCaml variant constructors (e. g. "Upper then lowercase"). The style may also be called pothole case, especially in Python programming, in which this convention is often used for naming variables. Illustratively, it may be rendered snake case, pothole case, etc. When all upper case, it may be referred to as screaming snake case (or SCREAMING SNAKE CASE) or hazard case.). These properties relate all characters in scripts with differing cases to the other case variants of the character. As briefly discussed in Unicode Technical Note #26,) in the 8th century. Over time, uncial letter forms were increasingly mixed into the script. The earliest dated Greek lower case text is the Uspenski Gospels (MS 461) in the year 835. The modern practice of capitalising the first letter of every sentence seems to be imported (and is rarely used when printing Ancient Greek materials even today).