A bucket toilet is a basic form of a dry toilet whereby a bucket (pail) is used to collect excreta. Usually, feces and urine are collected together in the same bucket, leading to odor issues. The bucket may be situated inside a dwelling, or in a nearby small structure (an outhouse). Once the basic bucket toilet has been "improved", it evolves into a number of different systems, which are more correctly referred to as either container-based sanitation systems, composting toilets, or urine-diverting dry toilets.