Just below the character box on the left side of the game interface is your Messages Pane. This is a very, very important part of the game because it tells you what is going on - not only what you are doing, but what is happening around you.
The message pane will automatically update without you reloading the page. This is so that you can do things (like, say, brew potions) while still being able to see if you are being attacked, or if other people say things, or whatever.
New messages - things that have happened since the last page reload - are bolded. Older messages - ones you have read - will be greyed out and in a smaller font. The message pane will include all of your unread messages and the twenty most recent read messages.
The message pane scrolls. You can scroll up or down to see what happened recently and catch up on conversations (or see who exactly was it that killed all your zombie pets).
Each message is stamped with a time when it occurred. By default, this will tell you "how long ago" the event happened, but you can switch that (in your preferences) to show real times (like in the screen shot).
If the same thing happens multiple times, the messages will be "collapsed" into a single line. For example, in the screen shot above, the message "You spend some time and effort reinforcing the barricade" happened four times in a row. If you like, you can click the plus icon (
) and the area will expand, allowing you to see the each message.
The message pane always loads in consistent size. This is so that the rest of the game interface doesn't "move around" on you while you're playing. You can increase or decrease the size of the pane (using the buttons in the lower right corner) and it will remember the last size you left it at.
At the bottom of the message pane is the "Speech Control." This is how you talk to the people around you.
All you have to do is type what you want to say into the input field and you'll say that. By default, it is set to speak to "Everyone Present," but you can select individual characters (using the pull down) and whisper to them.
You can emote from here, too! Just start your speech with "/me" or "/em" (no quotes) and you'll do an "action". For example, if your character is named "Archon" and you typed this:
Everyone around you would see this:
Sometimes your speech options aren't available (for example, if you transform into a bat), and other times they may be different (if you've transformed into a wolf, you can growl). Later in the game, if you join a Cult, you may get the option to speak in a secret "Cult Language".