The rich usually get richer through shrewd investments and Amazon.com Inc. (AMZN)  founder and CEO Jeff Bezos is no exception. 

Bezos is estimated to have a net worth north of $160 billion, according to the Bloomberg Billionaire's Index, about 65% more than the world's second-richest man, Bill Gates, who has a net worth just south of $100 billion. 

So how does Bezos maintain his vast fortune, outside of making sure Amazon remains the industry disrupting behemoth that it has become? His investment portfolio may give some insight into that. 

Bezos' investment history goes back to at least 1998. While still struggling to get Amazon off the ground four years after its inception, Bezos invested $250,000 in Google (GOOGL) .

RS Components has mined information from Crunchbase.com to provide a visual representation into some of the companies in which Bezos has poured his money. 

Some of the highlights from Bezos' investment portfolio are his $112 million investment into Airbnb, his $200 million investment in education tech company EverFi, and his $37 million stake in Uber. 

Tech is the sector Bezos seems most comfortable investing in, with bets on a total of 11 companies. Utah-based computer software company Domo is his biggest tech investment with a $60 million investment. 

Despite his investments in tech, Bezos also appears comfortable stepping out of his comfort zone with a swath of investments from education to hospitality. 

Amazon and Alphabet Inc., the parent company of Google, are holdings in Jim Cramer's Action Alerts PLUS member club. Want to be alerted before Jim Cramer buys or sells AMZN or GOOGL? Learn more now.

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