Learn how to share your location on Facebook and let others know where you're at. This guide provides a step-by-step process for checking in.

Imagine seeing the notification: "Mark Zuckerberg has just checked in at Madison Square Garden." Although you might not be friends with the Facebook CEO, if you were, this check-in would let you know he's at the iconic venue – great for meeting up if you're also at the same event.

In the age of smartphones, the check-in feature has become one of the most exciting new apps – it's not just about what we do, but where we are. According to research by ComScore in 2011, about 20 percent of smartphone users have adopted this app. Facebook Places is the leading platform, with Gowalla and Foursquare also being popular choices.

What is Facebook Places? It's a service that allows you to share your location with your social network. Initially launched for the iPhone, it now works on other devices such as Android and BlackBerry. To use it, simply download the Facebook app on your smartphone. If your phone has GPS, Places uses it to detect your location and potential places for check-ins.

If you don't have GPS on your phone or want to use Places on your computer, visit touch.facebook.com. You'll still need internet access, but Places was designed with mobile users in mind. After all, you're unlikely to carry your laptop to places like clubs, movies, or events [source: Miller].

Why should you use Facebook Places? Beyond satisfying curiosity, it has many benefits. You can find friends nearby and set up impromptu meetups. You can also stay updated on events — for instance, if your friends check in at a concert, you can join them. Plus, there are perks like saving money if you join a friend at a sale they checked in at.

However, there's a downside: Checking in at places like the movies can reveal your home is empty and for how long. This can lead to issues like cyberstalking or even real-life stalking. Plus, businesses can use your check-in info to send you unwanted offers. Use this feature wisely and with caution. We'll show you how to check in safely next.

Facebook Places

Facebook is a dominant force in the social networking world, with approximately 750 million users [Source: Facebook]. In comparison, Foursquare reached 10 million users by June 2011, but has a long way to go before rivaling Facebook's reach [source: Tsotsis].

Facebook has always allowed users to share their locations, but now it connects you to specific venues. Here's how you can do it:

As Spiderman's uncle, Ben Parker, wisely said, 'With great power comes great responsibility.' Facebook Places follows this principle. There are several privacy and security features to control your check-ins.

You can adjust who sees your check-ins. Use the 'Hide this from' option in the 'Custom' tab under 'Privacy Settings' to keep certain people, like your boss, from seeing your check-ins. When it comes to friends, Facebook will notify you if someone wants to check you in. If you approve, that friend can check you in with them. However, by granting approval, you also give check-in permission to any friend at any time [source: Ortutay].

Like many features on Facebook, Places is easy to start but tricky to disable. If you want to turn it off, follow these steps. First, go to your account's 'Privacy Settings':