I love to shop to Walmart I wonder if it is the largest corporation.
It depends on how you measure the size of a corporation. I believe that Apple is worth the most money amongst corporations.
But it must be in the top 10, I can't imagine a bigger grocery retailer. 
Yeah it's quite big. I like going to Walmart to people watch.
The corporation does not only operates Walmart, it also operates Sam's Club. I wonder which other store it operates.  
I know it just bought an online retailer in India to compete with Amazon. I can't remember the name though.
I think it is Best Price. I suppose it has also operations in Japan.