Facebook is making itself better to compete better with Google+. As a part of this, it has introduced a new feature "Subscribe".
It wasn't easy before to control what you see in your News Feed. It's obvious that you'd like to know more about your close friends rather than ex-colleagues. There was no option to get feeds from people who aren't friends.Subscribe option is a solution to all these. It'll be present on the people's profiles on the top right corner.
Facebook has 3 uses for the subscribe button:
Choose what you see from people in News Feed
Hear from people, even if you're not friends
Let people hear from you, even if you're not friends
You're already getting your friends' posts in News Feed. With the Subscribed button, you can choose how much you see from them: All updates, Most updates, and Important updates only(Just Highlights)
You can also choose what types of contents you see from a profile, which is optional.
Subscribe to Interesting People
You can now get public feeds from people who aren't your friends. You can just click on the Subscribe button to get updates(if public) about them in your News Feed.
You can choose what types of contents you want to see here too.
Get Your Own Subscribers
If you'd like to share your public updates with more than just friends, you can get a Subscribe button on your profile, too. People who subscribe to you will get posts in their News Feeds only when you set the update as "Public". This feature is also optional.
Once you allow subscribers, you can decide who can comment and what notifications you get. You'll also see a Subscribers tab on your profile, where you can see who subscribes to you.
Read the original content on Facebook Blog (Source). Check out more images on the Subscribe option below.