Part-of-Speech (POS) TaggingPart-of-Speech (POS) Tagging: Assigning grammatical tags (e.g., noun, verb, adjective) to each word in a sentence. This information is vital for understanding sentence structure and relationships between words. More: Assigning grammatical tags (e.g., noun, verb, adjective) to each word in a sentence. This information is vital for understanding sentence structure and relationships between words.