What is Market Capitalization ?
Market capitalization (market cap) is the market value at a point in time of the shares outstanding of a publicly traded company, being equal to the share price at that point of time times the number of shares outstanding.[2][3] As outstanding stock is bought and sold in public markets, capitalization could be used as an indicator of public opinion of a company’s net worth and is a determining factor in some forms of stock valuation.
Source: Wikipedia
Amazon leads the top with Market Cap of $450 billion followed by Walmart.
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