A full stop or period (sometimes stop, full point or dot), is the punctuation mark commonly placed at the end of several different types of sentences in English and many other languages. A full stop consists of a small dot placed at the end of a line of text, such as at the end of this sentence.
The term full stop is rarely used by speakers in the United States and Canada, but is the only term used in British English. If it is used in Canada, it may be generally differentiated from period in contexts where both might be used: a full stop is specifically a delimiting piece of punctuation that represents the end of a sentence. When a distinction is made, a period is then any appropriately sized and placed dot in English language text, including use in abbreviations (such as U.K.) and at the ends of sentences, but excluding certain special uses of dots at the bottom of a line of text, such as ellipses.
The term STOP was used in telegrams in place of the period. The end of a sentence would be marked by STOP, as using FULL STOP was costly. The end of the entire telegram would be noted by FULL STOP.
The word "period", although recognised as an Americanism, is used more broadly as an interjection to terminate a phrase or thought with finality and emphasis, as in "This is your last chance, period." The term full stop is also used in this sense in many parts of the world.