This book deals with the study of different types of cepstral feature extraction techniques, compare their performances and select best out of them. The best feature extraction technique is applied in the development of an acoustic-phonetic feature based Language Identification (LID) system using Phonetic Engine (P.E). A PE is a system used to capture the acoustic-phonetic information of the speech signal and to transform that into symbolic form. Automatic language identification is an important issue in the global community. The collaborations and trading between different countries are more and more popular. People who speak different languages must be able to communicate seamlessly with each other. Thus, it is necessary to know the language with which we are dealing, a LID system can help to lower the communication barriers among people from different regions.