Combinatory Categorial Grammar (CCG) is a type of formal grammar used in computational linguistics and natural language processing. It combines elements of categorical grammar and combinatory logic to analyze the structure of sentences. CCG focuses on how words can be combined based on their syntactic categories, allowing for flexible sentence constructions. In CCG, each word is assigned a category that indicates its syntactic role, such as noun or verb. The grammar uses combinatory rules to combine these categories, enabling the generation of complex phrases and sentences. This approach helps in understanding the relationships between words and their meanings in a sentence.