Objects are classified into three types, based on the ability of light to pass through them. They are transparent, translucent and opaque.
1. Transparent -The objects which allow all the light to pass through them are called transparent objects. Examples: water, air, glass etc.
2. Translucent - The objects which partially allow the light to pass through them are called translucent objects. Examples: Butter paper, vegetable oil, frosted glass etc.
3. Opaque - The objects do not allow any light to pass through them. They make a dark shadow when light falls on them and are called opaque objects. Examples: Wood, table, wall, pen etc.
Frosted glass is considered as a translucent material because it partially allows the light to pass through it.