Language acquisition is the process of acquiring the capacity to perceive and comprehend language, and to produce and use words and sentences in order to communicate. It involves the acquisition of structures, rules and representation. A range of tools like phonology, morphology, syntax, semantics and an extensive vocabulary is needed to successfully use language to communicate. Language can be used vocally as in speech, or manually as in signs. Humans have the capability to utter and understand an infinite number of sentences, based on a principle called recursion, even though human language capacity is finite. This book includes some of the vital pieces of work being conducted across the world, on various topics related to language acquisition. From theories to research to practical applications, case studies related to all contemporary topics of relevance to this field have been included herein. Students, researchers, experts and all associated with language acquisition will benefit alike from this book.