Some materials have the ability to change shape or size simply by adding a little bit of heat, or to change from a liquid to a solid almost instantly when near a magnet; these materials are called smart materials. They are those materials that posses both intrinsic and extrinsic capabilities to respond environmental changes. They respond to changes in temperature, moisture, pH, magnetic Field, electric field, etc. Today, the cars that are being manufactured abroad have smartness or intelligence build into them. These cars, called smart cars.The incorporation of smart materials makes driving even in difficult climate or weather conditions easy and pleasurable. There are many possibilities for such materials and structures in the man made world. Engineering structures could operate at the very limit of their performance envelopes and to their structural limits without fear of exceeding either. These structures could also give maintenance engineers a full report on performance history, as well as the location of defects, whilst having the ability to counteract unwanted or potentially dangerous conditions such as excessive vibration, and effect self repair.

The advantages of using smart materials include the following

1. Large actuation displacement

2. Large recovery force

3. Variable shapes

4. Usable in clean room environment

5. Noiseless operation

6. Intrinsic sensory capabilities