Butane is not a bad fuel, just a less practical one in real life for many of us. Among other things, it’s often more costly, [and] not as easily or widely available in larger-sized tanks… – P. Rowe1)
Butane (not to be confused with isobutane) is the most popular gaseous fuel after propane. Fuel is available with other camping supplies. 8oz Butane canisters are also available, and often cheaper, in Asian grocery stores where they are popular for countertop stoves.
Butane is not practical for use below freezing – it won't vaporise below ~33F2).
Stoves are available which will burn either propane bottles or butane canisters.
As with all fossil fuels, burning butane cleanly releases water vapor and CO2.3) The former can increase interior humidity.
As with other fossil fuels, burning butane in low-oxygen environments will emit carbon monoxide.4)