Most modern CPUs implements hyper threading or a similar technology which makes each physical CPU core appear as two logical cores on a system. In this manual the term "core" always refer to a logical core unless otherwise stated.
For static licenses, there is a limitation on the number of logical cores on the computer. If there are more than 64 logical cores, the CLC Genomics Workbench cannot be started. In this case, a network license is needed (read more at http://www.qiagenbioinformatics.com/support/licensing/).