Google famously has over 200 ranking factors in its algorithm, and has never (and will never) reveal the exact secret sauce, but that doesn't stop people from trying to crack it.
Regardless of how many signals marketers can put their fingers on, Google will never reveal how much weight is given to each one. Google also makes multiple changes every single day, and will always be multiple steps ahead of webmasters.
Backlinko's Brian Dean discussed the factors in a list back in April.[via Entrepreneur]