Boggle is played with 16 letter dice in a small 4x4 grid with a lid. (Big Boggle is the same with a 5x5 grid and 25 dice.)

One player shakes up the letters real good, nudges them all down into the holes in the grid, and reveals the result and starts a timer.

Now all players attempt to form words as follows:

  1. Start at any letter, and move to an adjacent letter orthogonally or diagonally.
  2. Each letter follows the next as above.
  3. Do not repeat the same die within a word, though you can repeat a letter if it appears on another die.
  4. No proper nouns. The usual other odd cases are similarly prohibited.
  5. There's a minimum length limit, usually 3 in basic Boggle and 4 in Big Boggle, though more skilled wordsmiths may wish to up these by one.
At the end, all players compare their lists. Any word which two or more players found is worth nothing. Thus, there is an incentive to try to find unusual words and words you don't think others will find.

The scoring used for unique words can vary. One system scores one point for 3 and 4 letter words, two points for 5 letter words, three points for 6 letter words, four points for seven letter words, and so on, adding one for each additional letter. Another system uses the Fibonacci numbers; the points for words up to length 6 are the same, but 7 letter words score 5, 8 letter words score 8, 9 letter words score 13, etc.

At the 1999 National Puzzlers League convention in a game of Big Boggle that I was playing with about 8 other people, somebody found the word international. Yes, it was really there, and didn't repeat any letters. Interestingly, several other people found inter and national but nobody else put them together. This was one of the most amazing feats of word gaming I've ever seen, and the 89 points for a 13 letter word blew away any chance of anybody else catching him.