Whick is the greatest?

Of all the webmaster tools you use, which one would you rate as the best too that you cannot do without?

Temi, it is the Yahoo! Site Explorer for me.:

I agree with you about how excellent Yahoo site exploerere is, it updates backlinks about ever 12 hours?

Can you guys expand on this a little for the mebers who are not aware of this usefull tool.
Url, what to do etc.

Thanks.

Basically, there is the hurrah about PR, Google tool bar etc but Yahoo exploerer is a much more SEO tool for checking backlinks and measuring how strong a backlink is and backlinks is updated every day by Yahoo explorer unlike Google that update theirs every month.

Midi, you are right. My post was quite short and i don't want to be a liner. So besides the Yahoo! Site Explorer there are some very useful tools. For instance the www.backlinkwatch.com, wich display your backlinks and the referring anchor texts. It makes you possible to check your link polularity concerning different keyphrases. www.nichewatch.com is also very useful since it helps you to uderstand what you should do in order to gain the No1 ranking. If you are going to buy a domain or you feel the PR update fever you may find the www.digpagerank.com very essential.
It warms you if a given site has fake PR (displayed with red colour).hmy:

As this post is related to webmaster tools so I am asking this. This might be a stupid question but let me ask. I have tried many link directories to submit my site but at the end of form they asked to link back a url. Can you tell me how to do that. Where to Add that link on my site. Somewhere in head tag of my main page?

It is so simple just put anchor text code in Body of your page. You can create a separate page for this as well.