When deciding what material to use for making something, you need to know what properties (features) you need for the new object and what materials would fit those needs best.

For example, imagine that you are designing a new case for a smart phone: it needs to be light, cheap, easy to make, able to be colourful and yet strong enough not to break if it's dropped - you have to choose between, say, glass, metal, plastic and wood. Wonder what you'd choose.....?

Let's find out more!