The components

This is what you get when you remove the 4 small screws of a 1991 portable disk player. Above you'll see the 5 main components of the Discman. The first being the rather large screen in the front, which is controlled by the motherboard below. Speaking of the motherboard, thats the green chip that everything else is planted on. Signals from certain button strokes, or electrical imputes travel through the different components to make everything work.
<------------- Here you can easily see the cover, which contains part of the 3rd main component, the buttons. Each physical button on the case, is linked to a small post that moves down when pressure is applied to the button, this then presses the small black button on the motherboard, telling the different components what to do.

This is the 4th main component, the laser reader. Some of the earlier form of CD's were actually called laser disks simply because they used this same form of laser reader, on a small moving mechanism. The laser shines onto the bottom part of a CD, reading it, and sending signals, once again, through the motherboard.
Lastly there's the battery compartment, and standard power jack. Either one of these will power the entirety of the device.