RULES..

• Plants vs. Zombies takes place on a lawn divided into rows and columns. Just beyond the left edge of the screen is your house, while just beyond the right side of the screen is the street.
• At the top of the screen is a seed tray that displays your current amount of sun (we'll get to this later), as well as whatever seed packets you have available.
• Zombies slowly move from right to left, from the street towards your home. Your job is to stop the zombie attack by collecting sun and using it to buy various defensive plants to place on your lawn. If a zombie makes it all the way to the left side of the screen, the game is over.

• You score points by defeating zombies. The faster you send the zombies packing, the higher your score.                                                                                                                                            SUN                                                                                                                                   
• Sun is the primary resource in Plants vs. Zombies. All plants in the game are purchased with sun, so managing your sun supply is one of the most important keys to success.
• Sun occasionally drops in from the sky in 25-sun units. While useful, this natural source of sun is insufficient to mount a serious defense against the zombies. 
• The Sunflower grows 25-sun units of its own, and you'll have to plant enough of them to generate enough sun to defend your lawn.
• Sun units, either falling from the sky or generated by Sunflowers, eventually fall to the ground and vanish if they're not clicked.

         PLANTS AND PLANTING

• Plants are your warriors against the encroaching zombie army. There are many different plants with many different abilities. Some plants fire projectiles that damage zombies; some block or slow the zombies' progress; some destroy zombies and themselves in a single instant; and some have entirely different functions.
• Plants are planted from the seed tray at the top of the screen. All plants cost some amount of sun to plant. Note that any available seed packs take time to recharge.
• A recharging seed pack is grayed out as it recharges. When the seed pack is fully recharged, it lights up and you can plant it again.
• The Sunflower will always be the first plant in your seed tray. You will be free to choose the remaining plants in your arsenal.