This section of the profile contains the member's wall, a space where other members can leave comments and messages. The wall is just one of many Facebook applications.

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Facebook Applications

Facebook's applications set it apart from other social networking sites. Facebook's first-party applications include photos, videos, groups, events, marketplace, posted items, notes and gifts. These are applications developed by Facebook and available to all members. Here's a quick breakdown on what each application does:

  • The photos application allows you to upload as many images as you like. If you have a picture of another Facebook member, you can tag the photo with that member's name. After tagging the photo, it'll appear both in your photo album and on your friend's profile.
  • Facebook's video application is similar in many ways to YouTube. Members can upload videos in almost every format, but Facebook requests that all files remain below 100 megabytes and that videos be shorter than two minutes. Facebook converts videos into the flash (.flv) format.
  • With the groups application, you can join other members' interest groups or you can create one of your own.
  • The events application allows you to invite other Facebook members to a real-life gathering.
  • Facebook's marketplace is a lot like craigslist -- it lets members connect with other people who want to buy or sell stuff. All transactions occur directly between members -- Facebook only hosts the exchange; it doesn't get involved in sales.
  • The posted items application can be used to post videos, songs or anything else on a Web page to your profile. All you have to do is enter the Web page's URL into the post field on Facebook. The application generates a thumbnail of the target page that acts as a hyperlink. Your friends can click on the thumbnail to visit Web sites that you think are cool and interesting.
  • With the gifts application, you can send another member a virtual gift in the form of a small icon. There are dozens of gifts to choose from, all designed by Susan Kare, who created the icons for the original Macintosh computer system. The first gift is free, but all subsequent gifts cost $1 and require a credit card -- Facebook doesn't accept PayPal. Facebook donates proceeds from gift giving to charitable organizations. Gifts can be private or public, and you can include a message with your gift.

Facebook is always working on developing new applications for members. If you're familiar with Facebook, you know there are hundreds of other applications available on the site. Facebook didn't develop these applications -- other Facebook members did.

Many sites give users limited access to an application programming interface (API), which lets users develop applications using the host site as a platform. But for most of these sites, user applications aren't featured on the site prominently. Third-party Facebook applications can dramatically change your experience on the site, including a massive overhaul to your profile page. Your simple profile can transform into an exciting page that includes videos, product reviews, games and virtual pets. But there's also the potential for chaos -- if you activate too many applications on your profile, it will become a sprawling Web page that other members might find difficult to navigate.

In the next section, we'll take a closer look at how Facebook members can create their own applications.