A quotation is the repetition of one expression as part of another one, particularly when the quoted expression is well-known or explicitly attributed by citation to its original source, and it is indicated by (punctuated with) quotation marks. It may also be known as the direct use of specific language that comes from another source, using the exact same wording as the original source. Generally, in formal writing, one would "cite the source" of the quote.
A quotation can also refer to the repeated use of units of any other form of expression, especially parts of artistic works: elements of a painting, scenes from a movie or sections from a musical composition.
Reasons for using quotations 
Quotations are used for a variety of reasons: to illuminate the meaning or to support the arguments of the work in which it is being quoted, to provide direct information about the work being quoted(whether in order to discuss it, positively or negatively), to pay homage to the original work or author, to make the user of the quotation seem well-read, and/or to comply with copyright law. Quotations are also commonly printed as a means of inspiration and to invoke philosophical thoughts from the reader.
Common quotation sources 
Famous quotations are frequently collected in books that are sometimes called quotation dictionaries or treasuries. Of these, Bartlett's Familiar Quotations, The Oxford Dictionary of Quotations, The Columbia Dictionary of Quotations, The Yale Book of Quotations and The MacMillan Book of Proverbs, Maxims, and Famous Phrases are considered among the most reliable and comprehensive sources. Diaries and calendars often include quotations for entertainment or inspirational purposes, and small, dedicated sections in newspapers and weekly magazines—with recent quotations by leading personalities on current topics—have also become commonplace.
||It has been suggested that Misquotation be merged into this article. (Discuss) Proposed since August 2012.|
Many quotations are routinely incorrect or attributed to the wrong authors, and quotations from obscure or unknown writers are often attributed to far more famous writers. Examples of this are Winston Churchill, to whom many political quotations of uncertain origin are attributed, and Oscar Wilde, to whom anonymous humorous quotations are sometimes attributed.
Deliberate misquotation is also common, though this often goes unnoticed, usually because the misquotation is better known or because the misquotation better fits a situation. For example, the Star Trek catchphrase "Beam me up, Scotty" did not appear in that form in the original series—likewise, the famous Dirty Harry quotation "Are you feeling lucky, punk?" is actually a rewording of the original dialogue: "You've got to ask yourself one question: 'Do I feel lucky?' Well, do ya punk?" Also, Darth Vader in Star Wars says "No, I am your father." not "Luke, I am your father."
Quotations and the Internet 
Chiefly a text medium in the beginning, the World Wide Web gave rise to any number of personal quotation collections that continue to flourish, even though very few of them seem to facilitate accurate information or correct citation. On June 27, 2003, a sister project of the Wikimedia Foundation called Wikiquote was created as a free online encyclopedia of quotations in every language and it is the biggest single quotation collection in the world.
The increase of written means of informal communication brought about by the Internet has produced the practice of using quotations as personal flags, as in one's own signature block. This is most commonly seen in email messages and Usenet posts, while it is almost never seen in blog posts. Quotations are also popular as a user's personal message, a line under the user's nickname in some Instant Messaging clients (and here they often go uncited). In all these cases, quotations are usually included to give a glimpse of the user's personality, to make a statement of their beliefs, or to spread views and ideas.
The sheer bulk of online quotations, combined with more efficient search engines, has effectively made the Internet the world's quotation storehouse for different types of quotes, such as life quotes , love quotes, friendship quotes and many more, encompassing an unprecedented number of easily obtainable quotations. Though matters of accuracy still remain, features such as Amazon.com's Search Inside the Book and Google Book Search may serve to alleviate such concerns.
Copyright law 
|This section requires expansion with: U.S. and other countries' laws. (September 2011)|
Section 30(1) of the UK Copyright, Designs and Patents Act 1988 (apparently in transposition of Article 5(3)(d) of the EU Copyright Directive on "quotations") allows "fair dealing" with a copyright work for the purpose of criticism or review, provided that it is accompanied by a sufficient acknowledgement.
See also 
- Block quotation
- List of book titles taken from literature
- Maxim (saying)
- Musical quotation
- Nested quote
- Spin (public relations)
- Use–mention distinction
- See A Book of Misquotations, edited by Elizabeth Knowles, Oxford University Press, 2006.
- website with life quotes
|Wikiquote has a collection of quotations related to: Quotation|
|Wikisource has original works on the topic: Quotations|