HUD or Heads Up Display is a tool used by online card game players to display statistics of opponents game play at the table directly around their name. For skilled professional players, this tool is indispensable. The tool can be found at various online sources such as drivehud.com, etc.
When professionals play online card game online they often play several tables at a time. Many players will play 4-16 tables at once across several monitors. When you play this many tables and hands at a time, it is virtually impossible to keep track of the playing style of every opponent at the table. The HUD can help you keep track of the playing style of every opponent at the table. The HUD can help you to keep track of who plays how by just having a look at their stats before you act.
The hand histories for every hand that you play online are stored on your computer’s hard drive. These hands can then be imported into tracking software and compiled into a database. The HUD will then read this database along with the current hand histories for live tables and display the stats directly on the table to help card game players make quick decisions based on the playing style and weakness of their opponents without having to actually watch every hand closely.