There are actually very few sales people in stores or online who actually are aware of any differences between rattan furniture and wicker furniture. If many sales people do not know, this makes it even more unlikely that the majority of people looking to buy such furniture would know either.
Rattan is a type of vine that grows in South East Asian tropical forests. It is closely related to the palm tree and as with many vines, grows rapidly when subjected to the right, humid conditions. In fact, amazingly enough it can even group up to 15 inches in just one day; often growing to a length of more than 600 feet. It is naturally very strong and very flexible, especially when it is wet; making it ideal for shaping into furniture. Perhaps the best quality of all is that it will not rot. Usually the stem is used when making furniture with rattan, although there is a core inside the stem that can also be used.
When the core is extracted, it can be woven. The woven material, made from the stem is called wicker.
Wicker can be made from rattan. It can be made from other substances too, such as cane and bamboo. You will even find plenty of synthetic wicker used for furniture as well.
If you are looking to buy outdoor furniture, it would probably be best to buy synthetic wicker. To the common observer it looks the same as natural wicker, the difference being that it is much more resistant to the elements. Color does not fade when exposed to sunlight, and it will last indefinitely. Usually you will find synthetic wicker is either brown or beige, although there are some pieces of furniture using brightly colored wicker. The advantage of using synthetic wicker is that you can leave it outside even in the winter; you could not leave furniture made from natural wicker outdoors in this manner.
Indoor furniture is usually fine made from natural materials such as rattan or bamboo. They are both very popular choices these days, and you can find not only living room furniture but beautiful wicker bedroom furniture sets.