RAM is absolutely central in a computer, nothing goes anywhere but via RAM.
All input or output devices (keyboard/mouse, scanner, printer, monitor, ...)
all storage devices, hard disk, CD, floppy disk, digital camera, memory stick, ...
all first get or move their information to RAM before it goes anywhere else
under control of a program in the RAM containing instructions to the CPU
(Central Processing Unit), that controls the whole computer.
So RAM can be thought of as central to a computer.
Some might say the CPU is the most important component,
maybe it is, but it is not central, the RAM is.
Core storage was of several types: two, three or four wire;
depending on the number of wires that threaded each core.
The most successful was 3 Wire Core Storage.
Assuming you have read and understood that we can look at the exhibits in the museum.
We start with the System 360 core storage and then look at earlier and later core storage.