This book convincingly explains the origins of language, illuminating how speech influences our thinking, our behavior, and our relation to each other, thus providing us a deeper comprehension of the nature of language itself. Comprehension is considered as the driving force behind language evolution. The first relations between signs, sounds, and meanings and the origins of vocabulary and grammar are examined. It is accounted for what the earliest forms of communication have probably been like, how vocabulary gradually developed, and what the required mind and brain competences were.