In printing and writing, an ellipsis (plural: ellipses) is a row of three dots (…) or asterisks (* * *) indicating an intentional omission.

An example is, "She went to … school." In this sentence, "…" might represent the word "elementary", or the word "no". The use of ellipsis can either mislead or clarify, and the reader must rely on the good intentions of the writer who uses it. Omission without indication by ellipsis is always considered misleading.

Ellipsis can also used to indicate a pause in speech, or be used at the end of a sentence to indicate a trailing off into silence.

The Chicago Manual of Style suggests the use of ellipsis points for any omitted word, phrase, line, or paragraph from within a quoted passage. There are two commonly used methods of using ellipses: one uses three dots for any omission, the second makes a distinction between omissions within a sentence (using three dots: …) and omissions between sentences (using a period followed by three spaced dots: ...).

An ellipsis is also a rhetorical figure of speech, the omission of a word or words required by strict grammatical rules but not by sense. The missing words are implied by the context.

Typical examples of this are:

Pat embraces Meredith, and Meredith, Pat, in which the second instance of the word embraces is implied rather than explict.

And so to bed, which appears on several occasions in the diary of Samuel Pepys, meaning and so I went to bed.

Is there for honest Poverty
That hings his head, an' a' that;
(the opening of a poem by Robert Burns. Burns is asking:
Is there an honest man among us who hangs his head, and otherwise cringes, because of his Poverty?

"Wikipedia is the greatest encyclopedia ever created" which can be interpreted as a short way to say:"Wikipedia is the greatest encyclopedia that has ever been created"

(This could also be explained without using ellipsis. "Created" is a past participle, which modifies the noun "encyclopedia" in the same manner as an adjective ie "Wikipedia is the greatest created encyclopedia ever.)
The aposiopesis is a form of ellipsis.

In computer programming, the ellipsis is Unicode character 0x2026, which is displayed as "…". The HTML character entity for it is … (for 'horizontal ellipsis').