So if you invested in Apple a decade ago, you'd probably be feeling pretty good about it today. According to CNBC calculations, a $1,000 investment made in early August 2008 would be worth more than $9,222.50 as of August 2, 2018, or over nine times as much, including price appreciation and excluding dividends.

Apple shares hit a historic $1 trillion market cap value on Thursday, becoming the first public U.S. company to ever reach the milestone. The stock briefly hit the $207.05 per share price that was needed to bring Apple to the $1 trillion mark before retreating, CNBC reports .

Apple's all-time stock growth, as of August 2, 2018 at 12:36 p.m. (Click to enlarge.)

While Apple's stock has performed well, any individual stock can over- or under-perform and past returns do not predict future results.

Apple's recent surge allowed the software company to defeat e-commerce giant Amazon in the race to become the first publicly traded U.S. company worth $1 trillion.

Apple stock also soared in May, when Berkshire Hathaway chief executive officer Warren Buffett revealed that his company bought 75 million shares of Apple, adding to the 165.3 million shares it already owned.

Some analysts had concerns about a possible slowdown in iPhone sales after the company's quarterly earnings report showed Apple sold fewer iPhones than expected. But still, in his interview on "Squawk Box," Buffett said long-term investors shouldn't be too concerned about near-term iPhone sales.

"The idea that you're going to spend loads of time trying to guess how many iPhone X ... are going to be sold in a three-month period totally misses the point," he said.

If you're looking to invest in the next Apple or considering putting some money in the stock market, experienced investors like Buffett, Mark Cuban and Tony Robbins suggest you start carefully.

Begin with index funds, they say, which hold every stock in an index, offer low turnover rates, attendant fees and tax bills, and fluctuate with the market to eliminate the risk of picking individual stocks.

This is an updated version of a previously published story.

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Video by Andrea Kramar