It's possible to set a custom message that will appear alongside your name in other people's contacts in Lync. You may want to broadcast a message that gives more details about your availability, or to let others know about your award-winning cake recipe.
On a PC, you'll find a grey box just above your name, usually with What's happening today? displayed.
On a Mac, the equivalent box is below your name, with the slightly more functional message of Click to create a personal status message.
To remove your custom message, simply click on it and delete the contents of the message.