A soft brick . Is usually when you are stuck in a boot loop. Or wont boot past recovery. You can fix a soft brick.
A hard brick, means your phone wont turn on at all. It cant be fixed, and is basically a brick or paper weight.
If you use the right thing to root your device, there is little chance of a brick. Most of the time if you do brick would be a soft brick.
My advice is research what you need b4 you root. Make sure you know what you are doing and using the right root method for your device. And the same for if you install a rom. Make sure you have the right rom. The wrong rom could result in a brick.
Posted via the Android Central App