Learn in the textbookInput/Output and Procedures & Functions
DefinitionAn argument (引数) is a value you pass to a procedure or function when you call it, for it to use in its processing.
ExplanationSeen from the block's side, arguments are its input. The declaration lists the names to receive inside its parentheses, and the caller writes values in that same order to pass them in. Changing the values passed in gets a different result from the same block.
AnalogyIt is like setting the original and the number of copies on a copier and getting exactly that output. The original and the copy count are the arguments.