Sticky

1. When referring to a forum, sticky refers to a post that has been stuck to the beginning of a category. This is commonly done for messages that are important, popular, and/or should be read.  
2. A sticky can also refer to a sticky note, a message that is posted on a software program to help the user not forget something. There are also numerous available software programs that enable you to do this everywhere on your computer. These reminders are similar to the sticky or Post-it notes you may have on your desk.

Also see: Forum