Punctuation refers to the symbols used in writing to clarify meaning and indicate pauses or stops. Common punctuation marks include the period, comma, question mark, and exclamation point. Each mark serves a specific purpose, helping readers understand the structure and flow of sentences. Proper use of punctuation is essential for effective communication. It can change the meaning of a sentence; for example, "Let's eat, Grandma!" versus "Let's eat Grandma!" demonstrates how a simple comma can alter the message. Understanding punctuation helps convey thoughts clearly and accurately in written language.