An ICT system is a set-up consisting of hardware, software, data and the people who use them. It commonly includes communications technology, such as the Internet.
ICT and computers are not the same thing.
Computers are the hardware that is often part of an ICT system.
This is why your GCSE is not just about computers but about how, why and when people use them. It is the power of computers and communications that has allowed ICT systems to become so important. Like any piece of equipment, the important thing about it is what it lets us do.