Grip Tape is used to give a skater's feet more grip on the board. It usually has an adhesive back and a sandpaper like top.
The Anti Grip Tape is called Duckle. ITs the only grip tape that wont ruin your shoes... Check it out at www.ducklegrip.com
Heres one of mine, feel free to add your own.
Grip tape designs come in many shapes and forms, companys are making precoloured/cut designs for you to quickly and easily modify your griptape but with a little time and work, ok a lot of time and work, you can make a custom design of your own with your own grip tape.