Capital Community College Foundation
Guide to Grammar and Writing: The Apostrophe
What is an apostrophe? Where are apostrophes found in writing? Use this website to learn more about these crazy little punctuation marks.
SUNY Empire State College
Empire State College: Apostrophes
This resource looks at the three main uses of apostrophes: to take the place of deleted letters; to show possession; and to show plurals of letters, numbers, symbols, abbreviations and words used as words.
Online Writing Lab at Purdue University
Purdue University Owl: Possessive Pronoun and Apostrophe
This Purdue Online Writing Lab article explains the three uses of the apostrophe.