Jeffrey Williams presented on using the spaCy library for natural language processing. He began with an overview of key NLP concepts like tokenization, lemmatization, named entity recognition and part-of-speech tagging. He then demonstrated spaCy's features for these tasks and how to visualize outputs. Williams also showed how to apply spaCy to problems by extending its pipeline and training custom models. Finally, he reviewed alternatives to spaCy like NLTK, CoreNLP and cloud-based services from Microsoft and Google.