A coil mattress is made up with steel or metal coils inside. These coils are spread across the mattress which gives the mattress the required firmness & bounce. The mattress is topped with layers of foam which is distributed evenly. The foam acts as a padding which gives soft feel to the mattress. The more the number of coils inside the mattress can offer better support & firmness to the sleeper.
There is a significant amount of difference between Inner spring and a pocket coil mattress. The spring mattress is made up of steel or metal coils frame inside which gives it required support & firmness. These are considered to be old-school type mattress which then padded with foam to give it a necessary soft feel. On the other hand, Pocket coil mattress is made of up Individual pocket coils which are then sealed with a soft fabric from the outer side. These pocket coils act as an individual shock absorber which individually works on different pressure points thus minimizing movement on different part of the body.