This book highlights how the vocabulary is an essential aspect of language teaching and learning. Vocabulary is significant for teachers in teaching of any language as well as transacting the syllabus and also meeting the requirement and the need of effective teaching learning process. This study proves that knowledge of vocabulary breaks the barriers like low self esteem, low achievement due to blur and vague formation of sentences. It injects self confidence among students and teachers both. This study made it apparent that lack of sufficient vocabulary creates problem in communicating properly especially, where the conducive climate is not provided in language learning.