This textbook is designed to provide a detailed understanding of the principles and practices underlying the use of large language corpora in exploratory learning and English language teaching and research. It focuses on the largest and most representative corpus of spoken and written data yet compiled - the British National Corpus - and on the search tool SARA (SGML Aware Retrieval Application). The method adopted is to provide a graded series of exercises, each introducing at the same time new features of the software and new techniques or applications for computer-assisted language learning. The book also includes an overview of previous work in corpus linguistics, a bibliography, and a reference manual for the SARA software. * Graded self-paced tutorials * Suggestions for further work * Thorough coverage of corpus linguistics theories and practices * State-of-the-art software * Accessible non-specialist style