A carpet steam cleaner works like other steam cleaning devices do. Water is turned into steam and projected into the surface to be cleaned. The cleaning is the result of the steam and the added agitation produced by the brushes in the steam cleaner and the movements of the person using it. A steam cleaner gives a carpet a deeper cleaning than a vacuum can, since the steam cleaner can reach dirt and germs that are out of the vacuum's reach. Steam is good at killing many things, some of which are germs, bacteria, fleas, and flea larvae. So using a steam cleaner on your carpet will leave it more sanitary than a regular vacuum. Steam cleaners can also be used on your furniture and may also come with attachments to use on hardwood or tile floors.