Cleaning essentials (usually liquids, powders, sprays, or granules) are used to remove dirt including dust, stains, bad smells and clutter on surfaces. Purposes of cleaning essentials include maintaining health, beauty of spaces, removing offensive odour and avoiding the spread of dirt and contaminants to oneself and others. Some cleaning agents can kill bacteria (e.g. door handle bacteria as well as bacteria on worktops and other metallic surfaces) and clean at the same time. Others, called degreasers, contain organic solvents to help dissolve oils and fats.