TSMC is the world's richest-company-by-market-cap example that manufactures chips designed by Nvidia and Apple.
Taiwan Semiconductor Manufacturing Company, usually called TSMC, was founded in Taiwan in 1987. It pioneered the dedicated semiconductor foundry model: customers design chips, while TSMC manufactures them for those customers.
This separation allows companies such as Nvidia and Apple to concentrate on chip architecture and product design without operating their own leading-edge manufacturing networks. TSMC produces chips for many other technology companies as well.
TSMC is not the same kind of business as a fabless designer such as Nvidia. It is also different from an equipment maker such as ASML. Its strategic importance comes from advanced process technology, large-scale fabrication, and a broad ecosystem of semiconductor customers.