EDIT The Full Stop (from Latin: punctum) is the most important punctuation mark. The dot on the baseline says: sentence ends here. It is widely used for declarative sentences, requests or mild commands. It is also set after abbreviations and initials.

History
The full stop was generally introduced during the educational reform implemented by Alcuin of York during the times of Charlemagne (around 800 AD).
Apparently, the ancient Greeks were the first to put a full stop in the modern sense of the word, i.e. on the baseline at the end of a sentence. At the onset of the 2nd century BC, Aristophanes of Byzantium put a full stop at the end of each concluded thought. At that time, the Greek language had no word spacing. Along with the Latin alphabet, this invention was not to be adapted from the Romans until later.

Synonyms
In American English, the full stop is called a period.
In British English, it is also called a dot.

Typography
The Full Stop is set right after the last character of the last word and with a wordspace before the next word. The use of two spaces after the full stop is a remnant of typewriter times and shouldn\'t be employed in word-processing anymore.

Full stops come in the shapes of circles, ovals, squares, rectangles and diamonds, matching the font they belong to. The full stop most commonly used is the round one.

German ordinal numbers In German, the dot after a number marks an ordinal, e.g.: 1. = 1st, 2. = 2nd etc.

see also
… U+2026 HORIZONTAL ELLIPSIS
。U+3002 IDEOGRAPHIC FULL STOP

 jsw  080330 

EDIT English decimal number separator In English, the FULL STOP is used to mark the boundary between the integral and the fractional parts of a decimal numeral.

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