A laser is a thin beam of light. People use lasers all the time. You may have a laser at home. A DVD player uses a laser to read a DVD. A cashier uses a laser to read bar codes.
Photo Credit: ktsdesign/Shutterstock
In the Know
Ocean Scientist
Dr. Sangeeta Mangubhai is a scientist. She grew up on … read more
In the Know
Special Money
The United States Mint makes the money we use. The … read more
In the Know
Memorial Day
Memorial Day is a holiday. It is a day to … read more