English as a second language refers to the use of English by individuals who speak a different native language. English language teaching courses provide comprehension into English linguistics as well as spoken English. English has become a common medium of interaction between various regions, professions, dialects, cultures, etc. leading to the development of allied concepts such as English for academic purposes, English for specific purposes and international English. This book explores all the important aspects of English language teaching in the present day scenario. Students, researchers, experts and all associated with English language teaching and learning will benefit alike from this book.