The term "transferable skills" describes any skill or talent that can be taken from one kind of job to another. Its opposite is specific or dedicated skills. So a specific skill might be when someone learns how to use a specific kind of computer software that is used only at one workplace. Since that software isn't used anywhere else, knowledge of how to use it isn't a transferable skills. But the same worker, in the process of learning how to use that software, might also have learned a lot about how to use computers. That knowledge of how computers work IS a transferable skill, since it can be valuable in a lot of different workplaces.
