SEO and Google Says

SEO - Search Engine Optimization. Is to improve how high up your site is in the search engines.

Google-Says full article

Domain names:
"Google Says: [0099] Certain signals may be used to distinguish between illegitimate and legitimate domains. For example, domains can be renewed up to a period of 10 years. Valuable (legitimate) domains are often paid for several years in advance, while doorway (illegitimate) domains rarely are used for more than a year. Therefore, the date when a domain expires in the future can be used as a factor in predicting the legitimacy of a domain and, thus, the documents associated therewith."

Hosting Files:
"Google Says: [0100] Also, or alternatively, the domain name server (DNS) record for a domain may be monitored to predict whether a domain is legitimate. The DNS record contains details of who registered the domain, administrative and technical addresses, and the addresses of name servers (i.e., servers that resolve the domain name into an IP address). By analyzing this data over time for a domain, illegitimate domains may be identified."

Images are checked for text nor javascript but:
"Google Says: Make sure that your TITLE and ALT tags are descriptive and accurate."

No link schemes:
"Google Says: Don't participate in link schemes designed to increase your site's ranking or PageRank. In particular, avoid links to web spammers or "bad neighborhoods" on the web, as your own ranking may be affected adversely by those links."