Piezo - electric materials are those that produce a voltage when deformed ( squeezed or bent) or produce a small movement when a voltage is applied. This is known as a TRANSDUCER.

They can be naturally occurring quartz or synthetic materials such as ceramics or polymers. They are normally coated with metal on either side so that wire connections can be attached

Make Sound

A thin slice of piezo-electric material is used in talking or musical birthday cards. When a voltage signal is sent across the material it moves/vibrate to produce a sound.

Detect Movement

They can also be used to detect sound or movement. A piezo can be stuck to a window. It the window is broken and piezo will move and generate a small voltage which can be used to trigger an alarm.

Create a Spark

If built in the right way these materials can produce enough of a voltage to produce a spark. They have been used in lighters for years.

Generate Electric?

Inventor of the clock radio, Trevor Bayliss, has come up with an idea to put piezos in the soles of shoes, so when you walk and bend the sole they will generate electricity.