Nonogram (aka Paint By Numbers)

[from havards website]

1. Paint some black cells such that they obey all numbers:
   
2. Each number determines a number of consecutively filled squares (called a cluster).
3. Each number sequence (row or column) shows how many clusters are there and the cluster sequence (naturally, each cluster is separated by, at least, one empty cell).
   

Solution:

To read more, go to the Wikipedia entry. Also check a similar puzzle, Solitaire Battleship.