CWBillow wrote:And nobody has thought to put all these in one code page, why?
Because a code page can only contain 256 characters. You know 1 byte has 8 bit and so you can code only 2^8 = 256 characters with 1 byte. That's the reason why code pages exist.
As the Wikipedia page I linked to also mentions, there is now the Unicode system which encodes all characters for all languages and even graphic, mathematic and symbol characters.
But most text files are still single byte coded files and not Unicode files. Also most fonts contain only certain code pages or even only parts of a code page and not the full Unicode character table. So there is always a problem when a conversion must be done from a text file (1 byte per character) to a Unicode file (2 bytes per character) and vice versa.
UTF-8 and ASCII escaped Unicode files are a mixture of text and Unicode files to be able to use the full range of Unicode characters, but encode the file content still with just a single byte per character for the most often needed ASCII characters. Only the real Unicode characters are coded with special character sequences. That reduces the file size a lot which is the reason why UTF-8 is used heavily for webpages: It supports all characters, but the HTML files are for many (especially European) languages only a little bit larger than when encoding it in ANSI.