Propane is a clean burning fuel that comes in a canister or bottle. Think of the gas BBQ grill and propane is what is in the gas tank. With most propane camping stoves you have the option of smaller more transportable canisters compared to a 25Kg gas bottle is not always practical. Propane is good as a fuel as it burns very hot. But it doesn’t work well at high altitudes and with all canisters, it is really impossible to tell how much propane you have left in the canister. So if you are using smaller canisters as a rule of thumb I would always take a spare just in case your canister runs out.