Travertine is a a form of limestone. Marble, by the way, is a form of limestone as well: metamorphosed limestone. Travertine and limestone have a strength and durability to withstand the ages – look at the amazing structures from the ancient Rome that still stand today.
Durability alone is not why this material is so commonly used on floors. Unlike it’s counterparts, travertine (and limestone, though not as often used as travertine varieties such as Durango Travertine from Mexico or Turkish Travertine) has a soft, smooth feel rather than the hard, slippery feel of marble or granite. You can find travertine in a polished form, but most installations for flooring use the honed finish.
Travertine has natural holes in the material, resulting during its formation. These holes are obvious in tumbled forms of the material, and give any area a nice, rustic look. These tiles are often used as accents or kitchen back splashes. Larger tiles are common outdoors.
Travertine is also more common in terms of residential flooring because of it’s durability. Marble is a far softer and more porous stone, so for high traffic areas that require little maintenance, travertine and limestone are top picks. Commercial installations should look into granite, the strongest of the materials.
For indoor installations, the most common travertine is honed, and filled. Filled means that the holes of the material have been filled with an epoxy that is meant to resemble natural colors that could pass as sediment in the stone. If you can’t find the color fill that you like, an unfilled tile can later be filled with the same or different grout than the one used between the seams of the tile.
Polished travertine is common in showers. These days you can find travertine slab fairly readily available, and it makes a great alternative for vanity tops and kitchen counters.