What Are Sitemaps?
Sitemaps are something many people have heard about, but not everyone understands. In layman’s terms, it’s a way of notifying search engines about all the pages in a website.
More specifically, a sitemap is an XML file containing a list of URLs, as well as additional information for each URL such as when it was last updated, how often it changes, and how important it is in relation to other site URLs.
Sitemaps are used to notify search engines about URLs available for crawling, allowing search engines to crawl the site more intelligently. They are especially beneficial on sites using Flash content (not normally processed by search engines) or which have areas not available through the browsable interface. Google, MSN, Bing, Ask and Yahoo! all support sitemaps, making it an easy way to submit a site for crawling.
Sitemaps are limited to 50,000 URLs and 10 megabytes per file. For large sites which exceed these limits, a sitemap index can be used to submit up to 1000 individual sitemap files. Bandwidth consumption can be reduced by compressing with gzip.
The following are sitemap submission URLs for major search engines:
- Google http://www.google.com/webmasters/tools/ping?sitemap=
- Yahoo http://search.yahooapis.com/SiteExplorerService/V1/ping?sitemap=
- Bing http://www.bing.com/webmaster/ping.aspx?siteMap=
In each case the complete URL to the sitemap file, such as http://www.example.com/sitemap.xml, appended to the address listed and must be URL-encoded, replacing / with %2F, : with %3A, etc.