1. A method comprising: using a server computer, creating and storing a first module name, a first indication of a first version, and a first signature for a first data model that is digitally stored in a digital electronic data storage unit; using the server computer, receiving a second data model from the data storage unit and identifying a second module name in the second data model; using the server computer, comparing the second module name of the second data model to the first module name of the first data model; determining that the first module name and the second module name comprise a same name, and in response thereto, identifying a second indication of a second version from a revision field of the second data model; using the server computer, comparing the second indication of the second version from the second data model to the first indication of the first version of the first data model; determining the first indication and the second indication indicate the same version, determining a second signature for the second data model; using the server computer, comparing the second signature for the second data model with the first signature for the first data model; determining from the comparison that the second signature and the first signature are different, and in response thereto, creating and storing a flag value in main memory of the server computer and specifying that the second data model is different; creating and storing digital data content including a first set of fields from the first data model; creating and storing a field mapping that maps the first set of fields to a second set of fields from the second data model; comparing content from first set of fields with content from the second set of fields and identifying at least one difference in content of the second set of fields from the first set of fields; and causing displaying, on a client computer, a difference indication that specifies the at least one difference.