There are mainly three types of leathers on furniture: Aniline, Nubuk, and Finished.
Finished leather: is the most common finish on furniture. Colors are more consistent, better stain resistant, and easier to keep clean. Thorough cleaning of the furniture to remove airborne contaminants, body oils and everyday soil with a pH balanced cleaner will greatly improve the furniture appearance. The use of high pH cleaners can cause premature aging. This is due to fluctuation in the pH that can damage the bonds that hold the leather fibers together. Wear, scuffs, abrasions, cuts, and tears can all be addressed, application of color and a 3M protective topcoat can return the furniture to a like new appearance. Leather panels on arms or headrest areas that have worn through or rotted from body oils can be replaced then dyed to match, restoring the furniture to be like new again.
Aniline leather: comes from the best hides and has one of the finest feels on furniture. Dyes used in coloring these hides provide transparency that highlights the graining or other natural characteristics; it is very comfortable and has a very soft feel. Pure Aniline leather is subject to fading and should not be placed in direct sunlight areas. It is also very susceptible to staining, which can be difficult to clean. Chairs and Sofas with heavy fading or staining can have the color restored, converting the unit to finished leather and providing many more years of useful service.
Nubuk Leather: is aniline leather which has a sanded or buffed surface with a fine nap; this creates its very soft and supple feel. As mentioned above aniline leather furniture should not be placed in direct sunlight to prevent fading. This leather is also susceptible to stains and collects soil, newspaper staining, and body oils more readily. This leather can be cleaned and color brought back.