To indicate a series of items in a sentence, which punctuation mark is typically employed?

The comma is the punctuation mark that is commonly used to indicate a series of items within a sentence. When listing multiple items, the comma serves to separate each element, making the sentence clearer and easier to read. For example, in the sentence "We need to buy apples, oranges, bananas, and grapes," the commas help delineate each fruit being listed.

This usage helps prevent confusion and provides a natural pause for the reader, enhancing comprehension. While other punctuation marks serve their own specific purposes, the comma is uniquely suited for creating lists due to its function in providing separation without completing a thought or sentence, which is exactly what is needed in a series.