This document defines and explains the common punctuation marks used in English, including periods, commas, semicolons, colons, question marks, exclamation points, quotation marks, apostrophes, hyphens, dashes, brackets, and capital letters. It provides examples of how each punctuation mark is used, such as using periods at the end of sentences and in abbreviations, commas to separate items in lists and introduce additional information, and quotation marks to indicate words being quoted.