To use the controls:

• Click on a puzzle piece in the lower frame to select that piece and/or to change its orientation (some pieces have eight orientations, some have four, one has two, and the "x" has only one orientation).
  
  
• Move the mouse over the puzzle board in the upper frame. Click when the piece outline is where you want it.
  
  
• To remove a piece from the puzzle board, click it -- either in the upper frame or in the lower frame.
  
  
• To clear the board, click the button in the lower frame. You can also change the size of the puzzle board by editing the High and Wide settings. The classic version of the puzzle requires exactly 60 monomino squares (6x10, 5x12, 4x15, and 3x20), but I'll let you try your hand at smaller versions.
  
  
• Play around. I hope that you will find the controls intuitive and easy to use.
  
  

Pentomino Trivia

• The pieces have names! Eff, Ell, Eye, Pee, Ess, Tee, Hugh, Vee, DoubleYou, Exx, Why, and Zee!
  
  
• There are over 270 thousand trillion ways to get the puzzle wrong (that is, 270,000,000,000,000).
  
  
• There are over 5000 solutions to the 6x10 puzzle, and exactly 2 solutions to the 3x20 puzzle.