I think you meant this, yeah?
The Man Who Solved the Market: How Jim Simons Launched the Quant Revolution https://www.amazon.com/dp/B07P1NNTSD/ref=cm_sw_r_apan_glt_FFDCMFZWYSK7QBRA7RQK
A little of both and lots of very large computers.
Want some ideas? There are several books on Simons and his crew.
https://www.amazon.com/Man-Who-Solved-Market-Revolution-ebook/dp/B07P1NNTSD