A document that contains parameters, identified by some special syntax, that are replaced by actual arguments by the template processing system. For example:

 Dear ,  would like to invite you
 to a party at  on  at 

Where the words in angle brackets are the parameters to be replaced by the name of an actual guest, etc.

More sophisticated systems allow repetition, where a section is repeated in a single output document using a list of inputs; conditional sections or (nested) inclusion of other templates.

See also class template.