
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
March is Music in Our Schools month. Schools celebrate music. … read more
Patriots’ Day is on April 17. It celebrates the Battle … read more
On November 4, something mysterious will happen. It will be … read more
© 2026 McGraw-Hill Education. All Rights Reserved.