Abstract
Gradwohl et al. (2007) gave a zero-knowledge proof for Sudoku that can be implemented physically using common tools like envelopes and bags, and the procedures are so simple that they can be executed solely by kids. In this paper, we work along with this direction, and first propose some simple physical zero-knowledge proofs for Nonogram (which was a very popular puzzle game in the 1990s). © 2010 Springer-Verlag Berlin Heidelberg.