Clines is an extension for Firefox browser that is a clone of Color Lines, a well known game for DOS.
With the mouse, you move balls from one square to another one in order to build lines (horizontal, vertical or diagonal). When a line contains 5 or more balls, the line disappear from the board and your score increases. Immediatly after your move, three new balls will appear on the board.
When you move a ball from one place to another, it will move from square to square horizontally or vertically to reach its destination. There must be a "path" beetwen the departure and arrival squares. Therefore, the difficulty of the game is to move the balls in a way that you don't get blocked by the new balls.
Each time you make a line, you will get some points. If you make a line with five balls, you will get 11 points. For six balls, it will be 15 points ; for seven balls, 21 points ; for eight balls, 29 points and for nine balls, 39 points.
You have the possibility to cancel the last move you made. It can be a good idea if you made a mistake or if you hope to get a better layout of the three new balls on the board. Each game you play, you can cancel three moves for free. The five next times, you will loose one point each time; the five next times, it will be two points each time, etc.