Apple's stock market value closed above $500bn (£314bn), cementing its position as the world's most valuable company.

Only six US firms have ever been worth more than $500bn. Oil giant Exxon was worth that much in 2007, Microsoft was briefly worth $600bn in 2000.

Cisco Systems, Intel and General Electric have all reached that mark.

The popularity of iPads and iPhones means Apple's sales and profits are growing at rates rarely seen in a company of its size.

Analysts forecast that the company could make a profit of $40bn this year. That's more than most firms generate in sales.

Apple has $100bn of cash in reserve on its books, and investors are hoping that it may give some of that back to shareholders this year as dividends or share buybacks.

It caps a remarkable turnaround for the iPhone maker, whose shares were once worth as little as $3.19 in 1997, when it faced the possibility of bankruptcy. The company's share price closed at $542.44 on Wednesday on the Nasdaq.

The company's revival under Steve Jobs, who died last year, came about first in computers and then the iPod music player, which was followed by the iPhone and iPad.

Source :bbc.co.uk