In less than 10 minutes, you can drastically improve your privacy online and protect yourself against unwanted and invisible tracking.
Note that these privacy safeguards will also be blocking some ads. EFF is working with online advertisers to try to convince them to provide real privacy protections for users, but until they agree to meaningful standards about online tracking, these steps will be necessary for users to safeguard their browsing privacy. Aside from removing ads, these changes won't affect your browsing experience on the vast majority of websites. It's possible, however, that a tiny fraction of websites may behave differently or break, in which case the easiest solution is to temporarily use a "private browsing" mode without the settings enabled, or a fresh browser profile/user with default settings.
Source: EFF. Read full article. (link)