Photos from Walmart's boom in the 1990s show how the retail chain took over the world
The first Walmart store opened in 1962 and it was the No. 1 retailer in the US by 1990.
The history of Walmart: How one man built a retail empire
In 1969, the company officially incorporated as Wal-Mart Stores, Inc., and became publicly traded a year later. By 1972, the ...