In terms of the number of allowed deployments, a license can be one of two types:
A machine license enables an unlimited number of deployments to a particular machine. You may want to use this type of license if you perform deployment to the same machine on a regular basis.
A deployment license enables a single successful deployment to a machine. You may want to use this type of license if you perform deployment to the same machine once or infrequently. If deployment under a deployment license fails, you can perform another deployment under the same license.
You can obtain a license key that corresponds to a number of deployment licenses.
When setting up a deployment operation, you can choose whether a deployment license can be automatically used instead of a machine license, or conversely.