Facebook is committed to enhancing the social experience online, which is currently helping many local businesses. Therefore, they have teamed up with partner websites like Pandora, Yelp and Microsoft Docs to share what you are doing on those websites with your friends on Facebook. They call this "Instant Personalization". When Facebook rolled this out, they automatically included your account to be accepting of this, so have set your account to an "opt-in" mode.
Facebook explains that in order to share this information, you would need to click on a Like button on the partner website. However, as pointed out by Mashable, the tool is on by default, so if you don't click a "No Thanks" button, the information you transmitted over that partner site will be shared.
If you want to opt out of or disable Instant Personalization, here's how:
In Facebook, go to Account (top right of your screen)
Click on Privacy Settings.
Click on Applications and Websites
Click on Instant Personalization, then click on Edit Settings box to the right of it.
Uncheck the "Allow" box you'll see on the next screen (pictured below).
The link will be on the application's business page on Facebook, and will look like this:
You will get this message: "You can prevent Yelp from getting any info about you. This will also prevent you from seeing Yelp if other people have it installed."
The ability to share goings-on on Facebook is fun, and it has helped several businesses get the word out. However, the decision is yours on how public you would like to be, so use this article as a tool should you decide to opt-out.