Question

What is the difference between transparent and opaque?

Answer 1

Transparent- An object that allow light to pass through it and you can see the objects behind your transparent material.
Example-Glass
Opaque-An object which does not allow light to pass through it and you are not able to see the objects behind your opaque material.
Example-Wall

Answer 2

Transparent objects are those objects through which rays of light can pass easily

For example - Water  and glass is the basic example of a transparent objects  

Translucent  objects are those objects through which only few rays of light can pass through it.

For example- A paper  

Opaque objects are those objects where no lays of light can pass through them.

For example- wood