# VASSAL Reference Manual Home > Message Format
## Message Format A Message Format allows module designers to specify the format of text messages that are generated by VASSAL at various times during play. Any word surrounded by $ characters represents a variable whose value will be determined when the message is generated during play. Click on the Insert drop-down menu for a list of available variables. Selecting one of the variables from the menu will insert it at the current cursor position. Available variables will vary depending on the component being configured. Some commonly-used variables are: playerName is the player's name as specified in the Preferences playerSide is the side chosen by the player from the Definition of Available Sides playerId is a combination of playerName and playerSide specified in the Global Options When a Message Format is used in conjunction with a particular Game Piece, then the Properties of that GamePiece can be used in the Message Format.