When I click my own Adwords I get gclid= appended to the URL. I notice that many other sites do not get this. Is there any easy option to hide this? Should I be trying to hide it, or will that break something? Also, right-clicking my ad and examining my URL there shows _sig= appended to this. I notice some do, but many other sites do not have this. Does anyone know what this is for?
You need to turn off 'Destination URL Auto-tagging' in your account settings to get rid of these URL parameters. They're used by Google analytics though, so leave them alone if you're using it.