Google’s new privacy policy will go into effect as of March 1, 2012. The new policy will be the same for all Google products and services and affects all the information Google has stored for your accounts. It also includes any information that will be gathered from March 1st forward.
To date, all of your searches and records of every site you visit stayed in your Google Web History. This Web History was kept separate from all other areas of Google. Everything will now be combined with the new privacy policy. If you want to keep your personal life private, you want to be sure to clear your Web History. If you don’t do this, your searches could tell everyone things like your hometown, age, health issues, sexual orientation and so much more.
The only way to stop Google from merging your Web History with your Google + or YouTube usage, you need to delete all searches in your Web History. You also must stop any future activity from showing up on your Web History.
You can do this by following these simple steps:
Start by signing in to your Google account.

After that, go to https://www.google.com/history

Next, click on the “Remove all Web History” button.

Now, all you need to do is click on “OK”.

Take note that not only are you removing information from your Web History, but you are also pausing it. The Web History will remain paused until you physically enable it again.
If your Web History is active, Google will keep all the information in it for an indefinite amount of time. However, when you pause the Web History, most of your information will be cleared within 18 months. Further, when the Web History is disabled, the search results that are customized for you will no longer appear. The Electronic Frontier Foundation (or EFF) has a guide entitled Six Tips to Protect Your Search Privacy that offers suggestions on how to reduce the amount of information Google stores on you.
Most people have more than one Google account, so you must remember to follow the above steps for each one. Two other things you need to remember are: 1. Removing and disabling your Web History will not stop Google from storing your information for their internal use, and, 2. If a law enforcement agency requests any information, Google will supply it to them.