The period (.) is used to mark the end of a sentence in English writing.

In English grammar, the period is the most common punctuation mark used to signal that a sentence has finished. It gives readers a clear stop, helping to separate ideas and make text easier to understand. Without periods, sentences would run together, making reading confusing and tiring. This use of the period dates back to ancient writing systems but became standardized in modern English during the 17th century. Today, it is a fundamental part of writing taught to all learners.