The best way to learn C is to first refer to some good book. Most of those who start programming start with C-language. It is a very simple but very powerful language. You can do simple math operations to something more dangerous like writing a boot virus , using C.
Books
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The best book for C is Herb Schild - The c++ complete reference which has the entire first part of the book dealing with C.
The manual for C is the The C Programming Language by Kerningham and Ritchie. It is very good for those who have practised little programs and want to test their language skills and improve them. This book has been written by the creators of C themselves.
Online help
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The know-how-to guide can be obtained here :
http://guideme.itgo.com/atozofc/
This is a good book and the authors deserves all the credit for it.
Tools
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There are many compilers out there, but for beginners i would suggest either to use Dev-C++ which can be obtained from here
http://kent.dl.sourceforge.net/sourc...pp/devcpp4.zip
Another is the Turbo C++ 3 Compiler which can be downloaded free, just google out for it.
I hope this information is enough.