Unsupported titles/`period`

Indicates the end of a sentence or, sometimes, the end of a dictionary definition
End of abbreviation.
etc. — “et cetera”

Mr J. Smith
Separates a number or letter from an item in a list.
A. New York, B. London, C. Paris.

a. New York, c. London, c. Paris.

1. New York, 2. London, 3. Paris.

I. New York, II. London, III. Paris.
Used between words, indicates paused, serious speech.
I. Don't. Wanna. Hear.
Some uses associated with numbers.
1. Indicates ordinal numerals
  4., IV. — “fourth”
2. (obsolete) Used after numbers, representing a cardinal number.
  100. — “a hundred”
(IPA) Indicates a syllable break.
Used in numbered section/subsection titles, separates the sections and subsections.
10.1.4.6 How to make a profit

10.1.4.7 How to keep your profit
Used in numbered images, illustrations, maps, graphs, etc.
Map 1.4 Distribution of tigers in Africa

Map 1.5 Distribution of elephants in Africa
Used repeatedly (as in: ........) in the index of a book, separates the chapter name from the page number.
Introduction..................................13

Chapter 1.....................................14

Chapter 2.....................................19
(Australian rules football) Used to separate a team's number of goals from its number of behinds, and sometimes from its total score.
Brisbane Lions 20.14 (134) defeated Collingwood 12.12 (84)

Brisbane Lions 20.14.134 defeated Collingwood 12.12.84

Usage notes

In English, the symbol . has various names, used in different contexts:

To signify the end of a sentence: period or full stop
- My name is John. — My name is John period (US) or My name is John full stop (UK)
For use as a decimal separator: point
- 3.45 — three point four five
For use of a thousand separator: — (not pronounced)
- There are 1.000 species left. — There are one thousand species left
In names in computing contexts (file-names, domain-names, and so on): dot
- john.smith@example.com — john dot smith at example dot com
To separate the chapter name from the page number: leader
- Introduction..................................13

Quotations

For quotations using this term, see Citations:Unsupported titles/`period`.

Symbol

.

A separator used with numbers.
1. In some counting systems, the decimal separator.
2. In some counting systems, the thousands separator.
(programming, computing, networking)
1. In various programming languages, the structure access operator.
  point.x — “the ‘x’ property of the ‘point’ variable”
2. In various programming languages, the string concatenation operator.
  echo 'I am currently ' . myAge(1981) . ' old.';
3. In various operating systems, the current directory.
  ls . — “list the contents of the current directory”
4. The class selector in CSS, which intends to format a class of an element. (a class can appear freely one or more times in a page, as opposed to the ID selector: #).
  div.quotedtext {font-style: italic}
5. A delimiter.
  1. Separates a file name from its extension.
    document.txt — “the file with the base name ‘document’ and the extension ‘txt’”
  2. Separates the parts of the domain name of a website (including the subdomain and the top-level domain).
    en.wiktionary.org — “the Internet domain name with components ‘en’, ‘wiktionary’, and ‘org’”
  3. Separates the parts of a version number.
    version 1.2.16
  4. Separates the parts of an IP address (IPv4).
    127.0.0.1 = localhost
6. (regular expressions) Matches any single character.
(chat rooms, Twitter) Used to prefix a message to prevent it from being treated as a command.
.@Tim needs to fix this problem ASAP

How do I leave the chatroom? – ./exit

Quotations

For quotations using this term, see Citations:Unsupported titles/`period`.

Synonyms

(decimal separator): , (in some counting systems)
(thousand separator): , (in some counting systems)

Letter

The letter E in Morse code.

A short signal, used to form Morse code text, together with - (a long signal).
Visual rendering of Morse code for E. (Latin)
Visual rendering of Morse code for Е. (Cyrillic)