Differences between sponge rubber and solid rubber

Sponge rubber and solid rubber
There are two types of rubber: foamed and non-foamed rubber.
Foaming means that the volume is increased by air bubbles.
Sponge rubber
Sponge rubber is a foamed rubber.
Due to the air layer, it is effective when weight reduction or cushioning is required.
It is also easier to follow the special shape of the object to which it is applied.
Solid rubber
Solid rubber is a non-foamed rubber.
As there is no air layer, it is effective where strength, durability and physical properties are required and where strong impacts occur.