Free linguistic software

suite for natural language processing (NLP)

Praat ( ; ) is a free, open-source computer software package widely used for speech analysis and synthesis in phonetics and other fields of linguistics. The software was developed and is maintained by Paul Boersma and David Weenink at the University of Amsterdam, and is compatible most major operating systems, including Unix, Linux, Mac, and Microsoft Windows. Praat has been used in linguistic research on endangered and minority languages, as well as for analyzing regional accents and phonetic variation.