This class can be used to generate multiple sitemaps crawling sites. It can crawl one or more sites to retrieve its pages and follow links recursively and determine the addresses of all pages to include in a XML sitemap. It can ignore given URLs to avoid crawling and including in the sitemap. The class uses the Curl extension multi-request support to retrieve multiple site pages at the same time. You can also notify such services as Google, Yahoo, Bing, Ask and Moreover about your sitemap update. The class may also notify Google, Bing, Yahoo, Ask and Weblogs when the sitemap is updated.