One of the sections on every Facebook member's profile is a forum called the wall. A wall is a place for your Facebook pals to share interesting photos, videos, Web sites, and character insights. By default, the only peoples' walls you can write on are your own and your friends'. But since walls are part of profiles, anyone who can view your profile can see your wall messages. You can think of walls as a 21st-century version of the dry-erase message boards they used to have in dorm rooms: an informal place to brag, tease, show solidarity, get attention, and occasionally impart useful information.
If you check out the Applications Directory (Finding Applications), you can find several Facebook applications (such as FunWall, SuperWall, and Graffiti) that let you add photos, video clips, and even "spray paint" on your friends' walls.
Because friendly jokes can sometimes get out of hand, Facebook lets you remove any wall posts you don't like (Responding to a Wall Post) and restrict who can see your wall (Controlling Who Sees Your Profile and Contact Info).
Writing on a friend's wall is a more public way of expressing yourself than sending your friend a message, because all your friend's friends will see your wall post. Good candidates for wall posts include thanks, congratulations, birthday greetings, and other tidbits your shared connections might find interesting or useful.
To write on your own wall, follow the steps below, but head to your own profile instead of a friend's.
To write on a friend's wall:
On your friend's profile, scroll down to the Wall section, where you should see a text box that says "Write something..." If you don't see the text box, you're out of luck: Your friend has restricted access to her wall.
Type your message in the text box.
If you want to add a link to an online photo, video, or Web site, click Share Link, fill out the box that appears, and then click Attach. You can't use this method to share photos or videos that are saved on your computer—they have to be posted online somewhere. If you want to upload photos stored on your computer, flip to Sharing Pictures.
You can skip the http:// part of the Web site address if you like—Facebook automatically adds it for you.
If you decided to share a link, choose which thumbnail you want to accompany your link. Facebook pulls a site description and a handful of thumbnails from the site for you to choose from. To skip the graphic, turn on the No Picture checkbox.
If you change your mind about sharing a link, click the "remove" link.
Click Post. Your message appears on your friend's wall.
Some Facebook applications (Facebook Applications: An Overview) let you attach additional stuff to the messages you post on people's walls. The Graffiti Wall application, for example, lets you decorate your friend's wall with virtual spray paint.
Write something on the poster's wall. Clicking "Wall-to-Wall" displays a history of your and your friend's posts to each other's walls, and lets you add a new post. Clicking "Write on [your friend's] Wall" skips the back-and-forth history and just lets you type in your post.
Send the poster a private Facebook message. Click Message; Sending Messages covers Facebook messaging.
Delete the post. You can delete any post from your own wall, no matter who posted it. To do so, simply click Delete, and then click Delete again in the confirmation box.
You can also delete messages you posted on a friend's wall. To do so, surf to that person's profile, scroll down to the wall post you want to delete, and then click Delete.