The cells in a Nonogram have to be colored or left blank according to the numbers given at the side of the grid to reveal a hidden picture. The numbers measure how many unbroken sets of filled-in cells there are in any given row or column. A clue of "2 3 2" would mean there are sets of two, three and two filled cells, in that order, with at least one white cell in between.

 
Let's look at this puzzle: There is one row and one column with sets of five cells. The grid is only five cells, so they must all be colored. Similarly, any rows or columns with zero clues can be colored white. This puzzle has no rows or columns with zero clues.

Next, let's look at the columns and rows with the clues "1 1 1". We know that between any set of filled-in cells has to be at least one white cell. The grid is five squares, so there is only one possible way to fill in these lines and columns.

Now there are four unfilled cells left. By looking at the clues, we know that there have to be sets of three filled-in cells. The only possibility is to fill in the remaining unfilled cells - done! Of course there are many more tips to discover as you go along solving Nonograms...