Language as defined a tool of Communication. Grammar has the foremost position in using the Language. For translating a sentence from one Language to other Parts of speech was the main aspect. While translating a sentence from English it only gives ambiguous. Natural Language Processing is a scientific field that consist of Artificial Intelligence and Computational Linguistics concerned with the interactions between computers and human (natural) Language. Brill's Tagger was the major theory of Post (Parts of Speech Tagging). In this article we can converse about Language and Linguistics and how Linguistics plays its task in Grammar, the practice of NLP using Linguistics, Tagging of Parts of speech with several taggers and models.