Early versions of search algorithms relied on webmaster-provided information such as the keyword meta tag, or index files in engines like ALIWEB. Meta tags provide a guide to each page s content. But using meta data to index pages was found to be less than reliable because the webmaster s choice of keywords in the meta tag could potentially be an inaccurate representation of the site s actual content. Inaccurate, incomplete, and inconsistent data in meta tags could and did cause pages to rank for irrelevant searches. Web content providers also manipulated a number of attributes within the HTML source of a page in an attempt to rank well in search engines.