A message is a nice way of showing the user some content. You could also use it as a mailbox or something for your game.

First you need to declare your message, it consists on an Identifier, Title, a A subtitle and the message body.

var messages={
"Title": "Some sample writing",
"Subtitle": "From Evelyn",
"Message":"Just look how easy it is!<br><img src='img/sample.png'>"

As you can see, you can also write HTML on them!

Next, to show them up in your game, yo just need the Display Message command.

"display message SampleWriting"

Each message has a close button so the user is able to close it when he's finished reading it.