The Basics...

Single User - Can be installed on two computers. One computer can access the software at a time. Sharing the license is automatic; if computer 1 is not using the license, computer 2 can access. If you leave the software running accidentally on computer 1, computer 2 can "Take" the license. This prevents stranding the license should you neglect to close it before going home, on vacation, etc.

Multi-User - Can be installed on any number of computers. The number of concurrent uses is equal to the number of licenses purchased. All license administration is performed in the cloud eliminating the need for a local server license manager. Multi-User allows licenses to be checked-out and length of checkout period to be set. Multi-User supports remote deployment.

More Details...

FunctionSingle UserMulti-User
Internet connectivity requiredIntermittentPerpetual
Activations2Unlimited (no need to deactivate when moving)
Concurrent use1Number of licenses purchased
License properties accessibleLicense portal (online)License portal (online)
License "take" enabledYesNo
Offline usage7 days2.5 hours (use checkout)
Checkout enabledNoYes
Max checkout periodn.a.30 days
Renewal period30 minutes15 minutes
Remote deployment supportNoYes