The FriendFeed API enables developers to interact with the FriendFeed web site programmatically. It is designed to make it possible for anyone to develop FriendFeed interface for a mobile phone, integrate FriendFeed into a blog or web application, or develop an application that makes it easier to post new photos to your feed.
When a third-party application wants to use the FriendFeed API to interact with FriendFeed on your behalf, it will ask for your friendfeed nickname and remote key. Get your remote key or learn more below.
A remote key is a kind of password that you can give to third-party applications and websites to let them interact with FriendFeed on your behalf. There are limits to what can be done using a remote key, which means it's a lot safer than giving a site your FriendFeed password.
Many sites and applications use FriendFeed's API to let you read and interact with FriendFeed through their service. These sites and applications need your username and remote key to prove to FriendFeed that you gave them permission to act on your behalf.
Giving a site your remote key is a lot safer than giving them your password, but you should still trust the site or application before giving them your remote key. While your remote key can't be used to delete your account or change your subscriptions, it can be used to share things through your FriendFeed account, and to see the items and comments that your friends share, even if they're in private feeds. That said, most applications and sites are trustworthy and they ask for your remote key only so they can use the information in ways you specifically request and allow.
Breakups happen. If you want to stop letting a site or application access your FriendFeed, you can reset your remote key at any time. This will disable the current remote key, just like if you changed the lock on a door. Keep in mind that if you gave your remote key to other sites or applications that you want to still have access, you'll need to give them your new remote key after you reset it. To reset your remote key, go to your remote key page and click on "Reset remote key".
The API is still really new, but check back here in the coming weeks and we'll put together a list of the most interesting and useful sites and applications that use the FriendFeed API to improve their user experience.
We're glad you asked! By all means take a look at the FriendFeed API documentation, and have at it!