1979

Sony begins selling the Walkman, a portable music device using tape cassettes.

The Walkman becomes a symbol of freedom and portability for young consumers long before the iPod.

3M invents Thinsulateā„¢ thermal insulation that traps body heat.

The material makes clothing less bulky.

Brothers Scott and Brennan Olson develop in-line skates by attaching polyurethane wheels to ice hockey boots.

They also add a rubber toe-brake to their new design. Four years later, they will launch Rollerblade Inc. and reinvigorate the sport of skating on dry land.