Always dry your tent before packing it away, or at first opportunity. Ground cloths are thick plastic or coated nylon which some campers place under their tents to protect the floor. Others put it inside the tent. I consider ground cloths unnecessary weight and complexity. When my floor gets a hole I patch it with rubber cement, nylon tape, or duct tape.
Punctures are rare since coated nylon tent floors are quite strong.
For the tropics a ground cloth might inhibit mold growth. If you do use one be certain it doesn't extend beyond the tent since that would catch rain and immediately create a silly surprise. Tents, Cooking, Fire , and Carbon Monoxide Never cook inside a tent. The combustion can poison your atmosphere, consume your oxygen, and sear your nostrils. You could pass out and never wake up.