You may also need to check that your server is serving documents with the right HTTP declarations. Developers need to ensure that the various parts of the system can communicate with each other, understand which character encodings are being used, and support all the necessary encodings and characters. Ideally, you would use UTF-8 throughout, and be spared this trouble. This section provides a little additional information on mapping between bytes, code points and characters for those who are interested.
Feel free to just skip to the section Further reading. These character sets contain fewer than characters and map code points to byte values directly, so a code point with the value is represented by a single byte with a value of There are other ways of handling characters from a range of scripts.
For example, with the Unicode character set, you can represent both characters in the same set. In fact, Unicode contains, in a single set, probably all the characters you are likely to ever need. However, the code point value is not simply derived from the value of the two bytes spliced together — some more complicated decoding is needed. UTF-8 is the most widely used way to represent Unicode text in web pages, and you should always use UTF-8 when creating your web pages and databases.
But, in principle, UTF-8 is only one of the possible ways of encoding Unicode characters. In other words, a single code point in the Unicode character set can actually be mapped to different byte sequences, depending on which encoding was used for the document. There can be further complications beyond those described in this section such as byte order and escape sequences , but the detail described here shows why it is important that the application you are working with knows which character encoding is appropriate for your data, and knows how to handle that encoding.
The article Character encodings: Essential concepts provides some gentle introductions to related topics, such as Unicode, UTF-8, Character sets, coded character sets, and encodings, the document character set, character escapes and the HTTP header.
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Copyright by Refsnes Data. All Rights Reserved. Most code points represent a single character, but some represent information such as formatting. This means that it encodes each code point with a different number of bytes, between one and four. As a space-saving measure, commonly used code points are represented with fewer bytes than infrequently appearing code points. UTF-8 uses one byte to represent code points from The first UTF-8 byte signals how many bytes will follow it.
This is best explained with an example:. UTF-8 represents this eight-bit number using two bytes. The leading bits of both bytes contain meta-data. The first byte begins with The 1s indicate that this is a two-byte sequence, and the 0 indicates that the code point bits will follow.
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