Generally, a single activation of Maple is meant for one computer. Most single-user licenses (academic, commercial, government, and personal) include two activations. These two activations would allow you to install Maple on two unshared machines, with the stipulation that Maple cannot run simultaneously on both computers. Student licenses, on the other hand, usually have only one activation.
If you don't have an activation for another machine, you can contact Customer Service, email@example.com, to inquire about eligibility.