On Twitter, can I send a direct message to someone I am following, but they aren't following me?

[appleeee<3]

Also, how can I write on someone's "wall" for Twitter. This is so confusing!

Thanks!

[sound_two]

On Twitter people an decide to follow you or not. ei receive updates about you.

Someone can follow you without you having to follow them. And Direct messages are just messages. When you right on their 'wall' you're just commenting on what they did and they don't have to follow you to do this.
I know it's confusing at first, but you'll get used to it with continued use.

[Kato]

To answer the question about direct messages: you cannot send somebody a direct message if they are not following you. But you can however send a public reply to them (using the @ symbol before their name) and ask them to follow you.

To answer about writing on someone's wall for Twitter: there is not "wall" on Twitter like Facebook. But you can send them a public reply, like I stated above, by adding "@" in front of their name. When they go to the "replies" tab they will see your message. This is the closest thing to somebody's "wall" on Twitter.

Tweet me if you need more help: @katocollier
http://www.twitter.com/katocollier