I have some ads om my site from some competitors, i want to put a filter, how to do this ? I have one example down here, it's ok ? (let's say my competitor is site.com)
yes, you are right. no need to put www or http:// just type in the name of the .com or .info etc. if you want a specific subdomain them you can block abc.site.com
go to the adfilter in your adsense account and put there the url of your competitor into the ad filter list.