Sitemaps (STM) are consider that they are an easy way for SEO professionals to inform search engines about their web pages on sites that are available for crawling. STM is an XML file along with additional metadata about each URL information regarding there updating with the last status of crawl. If your site contains dynamic URLS or pages the best way is to use a sitemap file to provide information about your site, sitemaps help spider to know what URLs are present on your site and about how often they change.

Web crawlers greedy of links and discover pages from links to Link jumps one site to another. STM are considering as an industry standard they complement this data to allow crawlers that support to pick up all URLs in the STM. Although sitemap does not guarantee that web pages will be included in search engine, but provide search engine a hierarchical way to do better crawl of your site.  You can find good information on sitemaps at www.sitemaps.org.

Precautions with sitemap file?

• You can create Google Sitemap within few minutes using the tool Google Sitemap Creator and submit it on Google.
• Do not use free STM generator tools. They might misuse your content and create scraper sites with your content.
• If you are using multiple STM and data is more than 10 MB you may compress your sitemap with Gzip.
• Your Sitemap index file must be UTF-8 encoded.
• If you are providing multiple Sitemaps, then you should create a Sitemap index file and then list each STM in index file. Sitemap index files may not list more than 1,000 Sitemaps and must be no larger than 10MB (10,485,760 bytes). The XML format of a STM index file is very similar to the XML format of a Sitemap file.
• Your Sitemap file must be UTF-8 encoded (you can generally do this when you save the file). As with all XML files, any data values (including URLs) must use entity escape codes for the characters listed in the table below.  For more good information you can view http://xml-sitemaps.org/spec/entity-escaping .