Facebook is a platform for sharing in a variety of ways. Private messages, chat and public commenting are all a part of the site. Content you create is shown to your friends immediately -- you cannot delay your posts to some time in the future. If you change your mind about something you've posted, just click the "x" in the corner to delete it.
All posts you create on Facebook appear on the site in real time. Once you hit the "Share" button on a status update, or hit "Enter" to send a comment beneath someone else's post, the item is immediately posted on the social networking site for others to see. Even private messages are transmitted in real time and cannot be delayed.
All posts have a time stamp associated with them. For the first minute after you post new content to Facebook, the time stamp beneath your post shows how recently the post was made in terms of seconds. For the first hour, the time stamp reflects how many minutes ago the post was made, and for the first day the time stamp shows hours. Older posts have an exact date and time stamp.
Post to Your Own Wall
You always have full access to your own wall and its content. Create a new post for your wall by clicking in the "What's on your mind?" field either at the top of your profile, or the top of the news feed on your home page. Hit "Share" to transmit the post, and send it to your wall. The content may also appear in your friends' news feeds as soon as it is posted.
Post to Others' Walls
You are only permitted to post on the walls of people on your friend list. Go to the profile of a friend, click in the "Write something" field at the top of the page and type a message or paste a link. Click the "Share" button to transmit the content, which appears on the wall of your friend immediately.