The document defines compounding as combining two or more words to create a new word, such as blackboard. Compound words can be written as one word, hyphenated, or as separate words. The meaning of a compound word is often different than the individual meanings of its parts. Compound words in English can take various forms depending on whether they are noun compounds, verb compounds, adjective compounds, or other types. The document also discusses different classifications of compounds such as endocentric, exocentric, copulative, and appositional compounds.