Do travel compression bags need a vacuum cleaner or pump?

It depends on the type. Roll-up and cube-style compression bags (like the OlarHike cubes and Amazon Basics roll-up bags) push air out by rolling or zipping, so no pump is required, which makes them the practical choice for trips. Vacuum-seal bags compress more aggressively but need a pump; many travel sets now ship with a small rechargeable cordless pump so you aren't tied to a vacuum cleaner.