There are many kinds of Laser Pointers : Red,Green,Blue,Yellow,Even White . Red Laser Pointer is the first widely used laser pointer . It's very expensive at very beginning , not like today : you can almost get one in 10 dollars .

After the "911 Attack on America"  (Terrorist attack on New York City and Washington DC on 2001-SEP-11 ) , the red laser pointer is forbidden by law , as the red point on the target is similar with the one from a terrorist's gun . In this case , nobody wants to play red laser pointers , and the price of the red laser pointer fell down .

The second generation laser pointer : Green Laser Pointer . It's popular today . The green ones are much brighter and more beautiful than the red ones . Does it have the same fate as red laser pointer ? No one knows.

Blue,yellow and white laser pointers are very expensive  today .They are the products for the future .