Warren Buffettchairman and CEO of the Omaha, Nebraska-based holding company Berkshire Hathawayis one of the most popular investors in the world, with one net worth north of $145 billion.

^{Image Credit: Eric Francis | Getty Images. Warren Buffett.}

However, like all successful investors, Buffett it had to start somewhere.

In his biography The Snowball: Warren Buffett and the Business of Lifeauthor Alice Schroeder recounts Buffett's early fascination with money—and an important lesson he learned from his first investment.

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Buffett got his first taste of entrepreneurship at the age of six when he started selling packs of chewing gum. “I would buy packs of gum from my grandfather and go door to door in the neighborhood selling this stuff,” Buffett tells Schroeder. “I used to do this in the evenings, mostly.”

Finally, the young entrepreneur moved into sales Coca-colaa more profitable venture that earned him a nickel every six bottles. Selling golf balls at Elmwood Park Golf Course and peanuts and popcorn at University of Omaha football games followed.

one day, Buffett I visited the library and came across a book called A thousand ways to earn $1000, which opened her eyes to the power of compound interest. Buffett wanted to try it himself.

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In the following year, 1942, 11-year-old Buffett had saved $120 to buy his first stock: Cities Preferred Service. He took his sister Doris as a partner and bought three shares for each of them for $114.75.

Unfortunately, the market bottomed out in June and Cities Service Preferred fell from $38.25 to $27 a share, a fact that Buffett's sister “reminded” him daily, Schroeder writes. So when the stock had recovered enough to make a small profit — $5 a share — Buffett sold.

Cities Service Preferred then rose to $202 per share.

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Buffett tells Schroeder that the experience was one of the most important of his life because it taught him three lessons about investing:

1. Don't get “too fixated” on what you paid for a stock.
2. Do not rush to sell for a small profit.
3. Don't invest someone else's money unless you know you can succeed.

The lesson has served Buffett, now 94, over the years. In August, Berkshire Hathaway exceeded $1 trillion in market value for the first time.