1. A method for use in changing a resource of a computer from a first version of the resource to a second version of the resource, comprising: digitally storing, on a portable medium, the second version of the resource and replacement information which identifies the second version, describes features of the second version relative to at least one earlier version of the resource, identifies the location of the second version of the resource on the portable medium, provides instructions for installation of the second version of the resource, describes at least one reason for the second version, indicates a type of change from other versions to the second version, and indicates the importance of the change from the other versions to the second version, digitally storing in the computer information identifying the first version, by computer, automatically determining which of the other versions is the first version, based on the results of the determining step, automatically determining whether to change the resource, and automatically changing the resource.