A default, in computer science, refers to a setting or value automatically assigned to a software application, computer program or device, outside of user intervention. Such settings are also called presets, especially for electronic devices. The Oxford English Dictionary dates this usage to the mid-1960s, as a variant of the older meaning of "failure in performance".
Default values are generally intended to make a device (or control) usable "out of the box". A common setting, or at least a usable setting, is typically assigned.
One use of default parameters is for initial settings for application software. For example, the first time a user runs an application it may suggest that the user's delivery address is in the United States. This default might be appropriate if more users of that application were in the US than any other country. If the user selected a new country, that would override the default, and perhaps become the default for the next time the application is used on that computer or by that user. Changing the default for the next run would involve storing user info somewhere, such as in cookies on the user's computer for an Internet application.
Using defaults involves two goals which sometimes conflict:
* Minimal user interaction should be required. Setting defaults to the most commonly selected options serves this purpose.
* Panel entry errors should be minimized. Using defaults will tend to increase errors, as users may leave incorrect default settings selected. In cases where the value can be verified, this is not a severe problem. For example, the delivery country can be checked against the street address or postal codes and any mismatch can generate an error panel displayed to the user, who will then presumably make the correction.
In cases where there is no clear majority and the results cannot easily be verified by other available information, such as the gender of the individual, no default should be offered. Note, however, that some software applications require that default values be supplied.
Answered by
Gyan Singh
, an ibibo Master,
at
1:47 PM on June 15, 2008