Metal frames : have a longer life but tend to need more maintenance than plastic ones. Some people can be allergic to certain metals. If you have sensitive skin please look for nickal frames or titanium frames
Plastic Frames : are typically lighter than metal. Some types of plastic contract and expand with temperature changes and need to be adjusted more often.
Stainless Steel : are now being used in frame material and are typically low of cost and also its very durable, anti rusting component and anti resistant to breakage. Titanium are now being used in frame material and are typically high of cost and also its very durable, anti rusting component and anti resistant to breakage. The main advertage of using Titanium optical frames is that it is not having metal allergy.
Combination Frames : consist of part plastic and part metal. Usually the front of the frame is metal and the temples or ear pieces are plastic, or the front part is plastic and the temples are metal. Choosing the proper lens material to go with this type of frame is essential.