The various drives for the computer are installed in areas of the case known as drive bays. You then connect ribbon and power cables to them. The ribbon cables also plug into the motherboard.
It sometimes seems as though computing power in your pocket is a relatively new phenomenon, but in fact there have been ultraportable computers since the 8-bit era. They started to become useful ...
Most laptops I've seen don't use cables to connect to the HDD, the connector is soldered directly to the motherboard. If you ask me, it's not a matter of Apple's cables being more prone to failures, ...