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copied!<p>Your question is very broad, I'll try to address some specific issues you raised, hopefully it will get you abit more sorted out.</p> <ul> <li><p>The <code>char</code> type can be though of as just another numerical type, just like int, short and long. It is totally ok to write <code>char a=3;</code>. The difference is that with <code>char</code>s the compiler gives you some added value. instead of just numbers you can also assign ASCII characters to a variable like <code>char a='U';</code> and then the variable will get the ASCII value of that character and you can also initialize arrays of character using literal strings like so: <code>char *s="hello";</code>.<br> This doesn't change the fact that after all char is still a numeric type and a string is just an array of numbers. If you'll look at the memory of the string, you'll see the ASCII codes of the string.</p></li> <li><p>The choice of <code>char</code> being 1 byte is arbitrary and is largely kept this way in C due to historical reasons. more modern languages like C# and Java define char to be 2 bytes.</p></li> <li><p>You don't need "another" type for characters. <code>char</code> is just the numeric type that holds a single singed/unsigned byte the same as <code>short</code> is the numeric type that holds a signed 16 bit word. The fact that this data type is used for characters and strings is just syntactic sugar provided by the compiler. <strong>1 byte integers == char</strong>.</p></li> <li><p><code>printf()</code> only works with chars since this is the way C was designed. it it was designed today it would possibly be working with shorts. Indeed in windows you have a version of <code>printf()</code> which works with shorts, it is called <code>wprintf()</code></p></li> <li><p>the type <code>wchar_t</code>, in windows, is just another name for <code>short</code>. somewhere in the windows header files there is a decleration like this: <code>typedef short wchar_t;</code> which makes this happen. You can use them interchangeably. The advantage of using the word <code>wchar_t</code> is that whoever reads your code knows that you now want to use characters rather than numbers. Another reason is that if there's a remote chance that sometime Microsoft will decide that now they want to use UTF32 then all they need to do is redefine the typedef above to be <code>typedef int wchar_t;</code> and that's it (in reality this will be quite abit more complicated to achieve so this change is unlikely in the for seeable future)</p></li> <li><p>If you want to use some 8-bit encoding that is not ASCII, for instance the encoding for hebrew which is called "Windows-1255" you just use chars. There are many such encodings but these days using UNICODE is always preferable. Indeed there is actually a version of Unicode itself which fits in 8-bit strings that is UTF-8. If you're dealing with UTF-8 strings then you should work with the <code>char</code> data type. There is nothing that limits it to working with ASCII since it is just a number, it can mean anything.</p></li> <li><p>Working with such long numbers is usually done using something called "decimal types". C doesn't have this but C# does. The basic idea of these types is that they handle a number similar to a string. Every digit of the decimal representation is saved using 4 bits so an 8 bit variable can save the numbers in the range 0-99, a 3 byte array can save values in the range of 0-999999 and so on. This way you can save numbers of any range.<br> The downside to these is that making calculations on them is alot slower than making calculations on normal binary numbers.<br> I am not sure if there are libraries which do this kind of thing in C. Use google to find out.</p></li> </ul>

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