Video credit to: PuzzleTeam - YouTube

To solve a nonogram, fill in tiles that match the number pattern in each row & column.

For example...

[ 1, 3 ] Means there has to be one tile on its own, a gap (of any size), followed by a group of 3 tiles. And nothing more.

Here is what that looks like...

The same is true for columns, and there are some easy patterns to look out for.

Rows or columns with zeros or the exact grid length are good starting points...

Finally, once all tiles are placed correctly, a picture and it's title are revealed...