Objects are classified into three types based on the amount of light that can pass through them. They are opaque objects, transparent objects and translucent objects.
Objects that do not allow light to pass through them are known as opaque objects. Light rays cannot penetrate through them. This means that one cannot see through such objects. Wood, stone, metal etc. are common examples of opaque objects.
The materials through which we can see clearly are called transparent objects. Transparent objects are the type of objects that pass almost all light to pass through them due to which the objects on the other side are clearly visible. Glass, water and air are examples of transparent objects.
Objects that pass light to pass through them partially are called translucent objects. Translucent means semi-transparent. Materials on the other side of such objects can be seen, but not clearly. Polythene, butter paper, thin plastic sheet and designed glass are common examples of translucent objects.