Shade some rectangular areas in the grid. Each rectangle should have sides at least 2 cell long. Different rectangles cannot touch each other even at a point. Numbers outside show the number of cells occupied by the rectangles in the corresponding row or column.
Grid control: Click the mouse button at the selected cell to change the color of the cell. Second click will put auxiliary cross sign, which doesn't affect correctness of the solution, but helps visually. You can also drag the content of one cell to another with the mouse. More details about grid control are at the help page.