The Wayback Machine - https://web.archive.org/web/20131029184520/http://www.lincolncentresource.com/Errors/Off-Center.html
Off-Center Strike
The image to the left is an example of a 2000 Lincoln Cent that has been struck off-center.
An off-center strike is a result of a coin being struck outside the collar. Unlike a broadstrike, the image is not in the center of the coin. The result of the punch usually results in a coin that is not circular.
Off-centers can vary in degrees of how far off-center they are struck. Collectors differ in the type of off-centers they desire. However, coins with full dates are usually more desirable than those without dates, or missing digits.