If you have been using one search engine for years (for example Google Inc) then that provider knows about what you have been searching for during the entire time. And that means that they know alot about what you have been thinking.
Thus we should diversify our use of search engines, or put something between us and them (startpage.com), or both.
The key points are:
In the quick search area, choose which search provider you wish as your default (I suggest DuckDuckGo). Note also the 'Manage Search Providers' button. You can add/remove from this list. The Tor Project (we shall install Tor later) recommends Startpage. You can add that from Manage Search Providers
Even better is to not use a search engine. If you know where you want to go, type it (https://...). Even better, if you go there often, bookmark it.
Note: for important places (bank, webmail etc.) you should always use a bookmark.
2014-05-10, Copyright CC-BY-NC, DTU Environment