The Editor’s Manual
Free learning resource on English grammar, punctuation, usage, and style.
Use a colon only after a grammatically complete sentence to introduce a list. Don’t use a colon between a verb and its object. Don’t use a colon after a title, heading, or caption for a list.
The serial comma is used before the conjunction (“and,” “or”) that marks the final item in a series. Using it is optional, but it can sometimes affect the meaning of a sentence.
A list may be horizontal or vertical. List elements must be consistently punctuated and capitalized. Use a numbered list when the sequence or number of items is important; otherwise, use bullets.
Use a semicolon in place of a period to join two closely related sentences. Also use it to separate list items that themselves contain punctuation.