If you use Google Chrome, Google will know every URL you type into the location bar. More than that, they will know (almost) every partial URL you type into the location bar. More than that, they will know every word or phrase you type into the location bar, even if you type it and then delete it before pressing enter. More than that, all this information can be linked with your main Google account, because Google sends your cookie along with every automatic search it performs from the location bar. Chrome keeps track of which google account you are logged into and uses that cookie to send along with its auto searches.