system
Given the following post, respond as if you're commenting on Reddit:
human
8 Bit computing?

What are the physical properties of a bit in computing?

Meaning why could most early advanced computers only hold 2\^8 integer values?  More simply, what were the physical limitations of the motherboard that mad it so 255 was the highest value reachable?

Further, how are we now able to achieve 64 bit computing, what physically has changed on the motherboard or otherwise?

&#x200B;

If this question is too convoluted what is a good resource where I can understand how motherboards work fundamentally? Other than wikipedia.
gpt
The number of bits in a processor word doesn't really come down directly to physical limitations, it's just a choice you make when you design the system. However, the state of technology does affect the cost-benefit trade-off. A 64-bit CPU requires more transistors and address lines and its programs require more memory to store. As transistors and memory have gotten much cheaper (in terms of both money and space), this is no longer a substantial cost. One of the main benefits of the 64-bit CPU is that it can address more memory, but due to the cost of memory this wasn't relevant in the 8-bit era. As such, the benefits of 64-bit have gotten greater and the costs have gotten less.