Block ciphers are the central tools for cooking up the largest portion of data encrypted in today's world. It is crucial that they must be efficiently implemented in both hardware or/and software platforms. Furthermore, error-correcting codes are used to "protect" the transmitted digital data over unreliable communication channel. People prefer to rely on well-known block codes, for example Hamming codes, Reed-Solomon codes etc., while LDPC (Low Density Parity Check) codes were ignored for 30 years from the moment Robert Gallager introduced them in his doctoral dissertation, 1960. Nowadays, LDPC codes are the opposite. They are the most attractive topics in coding theory. LDPC codes are usually long with a great probability to reduce the loss of information in a noisy communication channel. There are introduced very fast encoding and decoding algorithms which are implemented in Matlab. My work is to focus to implement this algorithms in C. The advantage of this approach is that you can quickly and easily analyze LDPC codes thanks to the speed and power of C.