When questions arise from conversations with friends and family and no one knows the answer, my go-to response is, “I bet Google knows.” Now, with personalized search results, the things Google knows for you may not be the same thing it knows for me.
How does the service differentiate between users? If you’re signed in to your Google account, Google uses your personal search history in order to rank more relevant URLs higher in search results. If you’re not signed in or don’t have an account with the service, then it uses an anonymous cookie placed on your computer to track your browsing habits and use these to influence your search results – for up to 180 days.
If you’re a card-carrying member of the Tinfoil Hat Brigade, then never fear – the service still offers ways to opt out of this potentially intrusive feature.