The branch of AI focused on enabling machines to understand, interpret, and generate human language. NLP covers everything from basic text processing (tokenization, stemming, part-of-speech tagging) to complex tasks like sentiment analysis, machine translation, summarization, and question answering. Before Transformers, NLP was a patchwork of specialized techniques. Now, LLMs have unified most of NLP under one paradigm — but the field's foundations still matter for understanding how and why these models work.
Why it matters
NLP is the reason you can talk to AI in plain English and get useful answers back. Every chatbot, every search engine, every translation service, every AI writing tool is NLP. Even if you never build an NLP system from scratch, understanding the fundamentals — tokenization, attention, embeddings, context — makes you a better user of every AI tool that handles text.