POS software mostly runs on one of three types of hardware: tablet, desktop PC or hardware that is a combination of both. Generally, you would need at least one device per register. Any device with a full-function operating system that connects to the internet works.
However, modern Cloud-based POS software, like TallOrder POS, run better on tablets due to the mobility afforded to them and their off-line capabilities.
Minimum Specs to Run TallOrder Point of Sale Software: