There are probably more than 100 rules that Google uses to rank pages in the search engine result pages (SERP). No one really knows all the rules, and they're changing on a periodic basis. Various confirmed and suspected SEO rules described here are educated guesses by SEO experts.
Positive Google Rules (On Page)
- Keyword in URL.
- Keyword in domain name.
- Keyword in title tag.
- Keyword in Heading tag (i.e. H1, H2, and H3).
Positive Google Rules (Off Page)