Google Webmaster Tools sitemap

Can anyone explain the reason for submitting a sitemap to Google Webmaster Tools.
Should you list all of the pages on your site?
Does it help with ranking or recognizing backlinks?

 

It helps indexing, nothing more.

 

A sitemap is a just a file (in xml format) that a search engine crawler can use to find more web pages on your website without having to crawl the entire sites link structure, they don't make indexing happen any faster.

 

I think you're wrong. If some pages are unfindable through links but it's still in the sitemap it can be indexed, which is faster than it never being indexed if you has no sitemap.

 

helps with indexing but also can help find hidden pages which have no links pointing to them, but would be strange to have a page in your site with no links to it.

 

It helps google bot to find all your pages

 

If you use a XML sitemap it can also be used to let the search engines know which are the most important pages on your site, when they were last updated and how often the pages change content.

 

In theory, even a web page not internally linked at all can be found and indexed, that is the nature of search engines and how they crawl sites. I've seen it happen many times on my own sites with test web pages I never link to and guess what they sometimes appear in the index anyways.

A sitemap is just a entire list of all available URLs, also if you don't have a web page internally linked no generator is going to find it to add to the sitemap anyways, unless you build the sitemap by hand.

 

Do you have Alexa installed? The rumor is that they share data with google.

 

Wrong, Alexa and Google do not share data. In fact that is one of the stupidest things related to Alexa I've heard so far in 2008. Alexa does share you data with marketing companies, considering Alexa toolbar is spyware.

Think about it, what is the definition of spyware? A program that collections and gathers data about your surfing habits and reports it back to a central database where that information is sold for marketing purposes.

So, Alexa has a nice way to convince people to use it's spyware toolbar with so called ranking information, which is funny since less than 1% of web users actually use Alexa, making the error in Alexa data around 99% inaccurate.

 

What happen if you put in the importance value of 1.0 for all your pages vs 0.5 for all the pages in your sitemap.xml file? Everything is important? Everything is not important? i dont quite get the idea for this.