GeneSpring WG_Client Fixed license is used on a single machine at a time. It is machine specific and gets locked with the machine on which it is activated and cannot be transferred to another machine.
GeneSpring WG_Client Floating License on the other hand is not machine specific and can be used on multiple machines simultaneously by connecting to the Floating License Server to be served an available license. The number of available licenses depends on the number of concurrent keys purchased with the floating license.