What is a sitemap?
Mostly used sitemap is in HTML format.
It contains list of all links present on your website.
This sitemap is generally for visitors of the website
to find the desired links quickly and it also helps search
engine spider to crawl and indexing of pages on your website.
Other type of sitemaps found in ROR, text, XML formats.
What is XML or search engine (Google, yahoo) sitemap?
Recently biggest search engines Google & yahoo introduces
own standard of sitemap i.e. XML sitemap and now ask.com
also support this format. Sitemap file include the lists
of all the URL's along with changes made for each, change
frequency & priority. Synonyms for sitemap are crawler-pages,
gateway-pages, hallway-pages, spider-pages.
This is How XML Sitemap Looks
Why XML sitemap?
Apart from the URLs sitemap contains other metadata about
links like change frequency, last modification date, priority
is also the part of sitemap.
Second thing, Visibility and indexation in search engines are most
important factors for website owner or administrator. Search engine
crawls only static contents and if you have dynamic links like javascript,
crawler will not take efforts to extract links. Another thing is suppose
you don’t want to put some URLs (say A) on your homepage or on the pages
that are directly or indirectly linked to homepage in this case when
crawling takes places search engine will not get navigated to these
links (A). In this case also XML sitemap plays important role.
So XML sitemap standard is made of search engines like Yahoo, Google,
MSN, Ask and it is the best way to inform SE about the webpages present
on your website. Web crawler will easily pickup links and other metadata
from it and easily navigate to even dynamic pages.