A language resource consisting of one or several dictionaries is called a lexical resource. A lexical database is a lexical resource containing an associated software environment database that allows access to its contents. Databases can be broadly categorized into custom-designed or general-purpose database. It typically includes detailed semantic, syntactic and phonetic information about words and multiword expressions. Lexical data also contains semantic and phonological relationship between words, as well as translation equivalents to and from different languages. Natural language processing applications, dictionary makers and consumers make use of lexical data. While understanding the long-term perspectives of the topics, the book makes an effort in highlighting their impact as a modern tool for the growth of the discipline. It attempts to understand the multiple branches that fall under the discipline of language and lexical data and how such concepts have practical applications. The readers would gain knowledge that would broaden their perspective about this field.