Philadelphia — In December 1999, Guinness World Records listed the 10 greatest inventions of the 20th century. The computer wasn't included. But the food-storage containers made by Tupperware were.

When Tupperware Home Parties introduced the party plan system in 1951 to sell Tupperware plastic container products, it used U.S. households as a platform for reaching millions of consumers. Now, the ...

"I used to take in $200 extra a month selling Tupperware in the mid-1980s when I was living in the Northeast," said Linda Solomon, a former Philadelphia social worker who didn't give her age, and who ...