Coplink is a police database (FI, reports, tickets, etc.) program that allows multiple agencies to share information. An example would be if agency A searches their database for the address of a person and the last contact they had with that person was 5 years ago and may not be current, but through coplink they can search other agencies databases so they could find that agency C contacted that person 1 month ago with a more current address and thus can have a better chance of finding that person. This is only one way to use coplink, but my understanding is that it is not a dispatch or CAD applicaton.