It supports classification, tokenization, stemming, tagging, parsing, and semantic reasoning functionalities.

[4] It was developed by Steven Bird and Edward Loper in the Department of Computer and Information Science at the University of Pennsylvania.

[5] NLTK includes graphical demonstrations and sample data.

It is accompanied by a book that explains the underlying concepts behind the language processing tasks supported by the toolkit,[6] plus a cookbook.

[7] NLTK is intended to support research and teaching in NLP or closely related areas, including empirical linguistics, cognitive science, artificial intelligence, information retrieval, and machine learning.