Yahoo! Search Content Quality Guidelines

Yahoo! Search Content Quality Guidelines - Yahoo

• Original and unique content of genuine value
• Pages designed primarily for humans, with search engine considerations secondary
• Links intended to help people find interesting, related content, when applicable
• Metadata (including title and description) that accurately describes the contents of a web page
• Good web design in general

Unfortunately, not all web pages contain information that is valuable to a user. Some pages are created deliberately to trick the search engine into offering inappropriate, redundant or poor-quality search results; this is often called "spam." Yahoo! does not want these pages in the index.

Yahoo! Considers Unwanted:

Some, but not all, examples of the more common types of content that Yahoo! does not want include:
• Pages that harm accuracy, diversity or relevance of search results
• Pages dedicated to directing the user to another page (doorway pages)
• Multiple sites or pages offering substantially the same content
• Pages that rely heavily on content or links to content created for another web site, such as affiliate content
• Sites with numerous, unnecessary virtual hostnames
• Pages in great quantity, automatically generated or of little value (cookie-cutter pages)
• Pages using methods to artificially inflate search engine ranking
• The use of text or links hidden from the user
• Pages that give the search engine different content than what the end user sees (cloaking)
• Sites cross-linked excessively with other sites to inflate a site's apparent popularity (link schemes)
• Pages built primarily for the search engines or pages with excessive or irrelevant keywords
• Misuse or inaccurate use of competitor or brand names
• Sites that use excessive pop-ups, install malware (i.e. spyware, viruses, trojans), or interfering with user navigation
• Pages that seem deceptive, fraudulent, or provide a poor user experience

source : yahoo