Apple became the first company to reach $1 trillion. A few other companies are vying to join it. 

Amazon (AMZN - Get Report) , Facebook (FB - Get Report) , Microsoft (MFST) , and Alphabet (GOOGL - Get Report) are the closest.

Watch our video to find out far away they are.

But as a quick refresher, market capitalization is just the technical name for the the market value of a company's outstanding shares.

And to figure it out you just multiply the stock price and by the total number of shares outstanding.

So if a stock is at $10 and there are a million shares outstanding, then the market capitalization would be $10 million ($10 x 1 million shares). Pretty simple.

But its important to use the market cap to value the size of the company - not the actual stock price. Too many novices presume that the higher the stock price, the larger the company and that's just not true.

So do a little math. 

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