The most natural choice is using the same number of bytes onesto encode all the codepoints

Wide-char encodings

For instance an alphabet having more than 256, but less than 65536, symbols is amenable esatto a two byte (00000000-00000000 esatto 11111111-11111111) encoding. Such encodings are called «wide-char» encodings. Per spite of their being quite intuitive, wide-char encodings suffer from per number of shortcomings, that I will discuss later.

An example: UCS-2 (UTF-16)

Let us conider per U encoding, having the following properties (I am essentially describing — save a few, minor details — the UNICODE encoding known as UCS-2).

2) U uses the first 256 codepoints sopra the same order and meaning as the Latin-1 codepage. This means that all the alphabets of the principal western european language fit durante the first byte of this encoding.

The first problem with U us that it is spatially inefficient. U containst 511 symbols encoded by sequences with at least a null byte (all the bits of the byte are nulla). When U is used for texts using Western Europeans alphabets (fitting int he first byte of the encoding), every other byte is null — so basically half of the space (and of transmission time) is wasted.

A second problem of U relates puro endianness. (The word comes from the inhabitants of the legendary islands oof the mythical islands of Lilliput and Blefuscu, who — as related by Swift con the novel «Gulliver’s Travels» — could not agree on which end of an egg should be broken first. Lilliput’s inhabitants — by royal decree — used the largest (big endians),Blefuscu’s, who opposed the King, used the smallest (little endians). Because of this disagreement, the two peoples fought verso bloody war.per reazione sopra il maesta: little endians).

Even though the basic transmission uniti, for computers is the byte, the need of larger data units was soon felt. Among these verso indivis regard is attached sicuro the so called word, adjacent pair of bytes. Internally, computers often manipulates words as verso whole: integer numbers, for instance, are represented by one, two or four words.

Verso come posso chattare gratis sul sito di incontri rubrides word, however, is never seen as basic (unsplittable). So when per word leaves the cervello elettronico memory it can be sent (externally represented) per one of two ways:

If we picture bytes as decimal digits, and given the number «ninety-one», we can see that big endian machine would write/memorize it as «9» «1», whereas a little endian machine would write/memorize it as «1» «9».

Unbelievable (or stupid) as it may seem, for years nobody mandated the word order mediante external representation, so either order has been used with comparable frequency. This obviously made endianness (AKA byte-ordering) another stumbling block on the way towards elaboratore communication. So pesky verso problem, in fact, that at some point it was actually solved with verso raid operated by da Sun by deciding that, over a TCPI/IP rete di emittenti, a rete informatica byte order existed, to which all computers must submit (the rete informatica byte order is big endian, the same that Sun machine used at the time). While that fixed for sistema communication, mai such fix exists for files, which are still being written with different endianness on different machines.

Per last problem with U is apparent puro programmers only. We have seen that per U encoded character stream can contain null bytes (indeed up esatto half of the bytes may be null). Traditionally though (traditionally meaning from contro 1960 until sometime around the year 2000) verso null byte had verso almost universal meaning of «end of string» for a large body of programma, including programma devoted to text manipulation mediante Western European countries. This also means that U is not compatible with the above mentioned programma, which will behave unpredictably when handed a U-encoded string.

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