Natural Language Toolkit

{{Short description|Software suite for natural language processing}}

{{Use dmy dates|date=September 2017}}

{{Infobox software

| name = Natural Language Toolkit

| logo =

| screenshot =

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| author = Steven Bird, Edward Loper, Ewan Klein

| developer = [http://www.nltk.org/team.html Team NLTK]

| released = {{Start date and age|df=yes|2001}}{{cite web|url=http://sourceforge.net/projects/nltk/|title=Project site on SourceForge|date=9 July 2001}}

| discontinued =

| latest release version = {{wikidata|property|edit|reference|P348}}

| latest release date = {{start date and age|{{wikidata|qualifier|P348|P577}}}}

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| latest preview date =

| programming language = Python

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| genre = Natural language processing

| license = Apache 2.0

| website = {{URL|https://www.nltk.org/}}

}}

File:Noun phrase chunking with NLTK.svg generated with NLTK]]

The Natural Language Toolkit, or more commonly NLTK, is a suite of libraries and programs for symbolic and statistical natural language processing (NLP) for English written in the Python programming language. It supports classification, tokenization, stemming, tagging, parsing, and semantic reasoning functionalities.{{Cite web |title=NLTK Courses |url=https://docs.google.com/document/d/1eYubSwLkpB7ZgfQVxxAwgsmAqS__BRfbMyP9qV6ngD8/edit |access-date=2016-06-15 |website=Google Docs}} It was developed by Steven Bird and Edward Loper in the Department of Computer and Information Science at the University of Pennsylvania.{{Cite web|url=http://www.nltk.org/book/ch00.html|title=Preface|website=www.nltk.org|access-date=2016-06-15}} 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, plus a cookbook.

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.

NLTK has been used successfully as a teaching tool, as an individual study tool, and as a platform for prototyping and building research systems. There are 32 universities in the US and 25 countries using NLTK in their courses.