system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How exactly does Apple make its mobile processors?

Apple has its own line of mobile CPUs (A7, A8, etc...), how are they made? Some people attribute it to Samsung, others to Apple themselves. Maybe TSMC? What role does ARM play? How does it work?
gpt
ARM is a company that designs the chips. Then another company buys the instructions to make ARM chips and can modify the design (Apple does this). Then Apple pays another company to actually make the chips using the instructions that Apple has modified. It used to be Samsung, but for their most recent devices TSMC made the chips. So only Apple will have the A8 chip that they designed, but they didn't design it from the ground up, nor did they physically produce it. The Apple chips are pretty fast though and keep pace with the rest of the industry despite only being used in one company's devices.