Apple has officially become the most valuable company of all time, with a market value of around $623bn, or £397bn. Adjusted for inflation, that figure's still tiny compared to IBM's $1.3tn valuation in 1967.

The tech giant is now worth around $200bn more than the world's second biggest company, Exxon Mobil, with the figure surpassing Microsoft's record of $620.58bn set in 1999. Back then Apple was only just returning to profitability after a decade in the doldrums struggling to compete with Microsoft's monopoly of the computer market. But with the return of founder Steve Jobs in 1996, the company launched a series of products that have come to define consumer technology of the last decade.

In 2001 Apple launched the iPod, a groundbreaking mp3 player that coupled with online music store iTunes changed the way people bought and listened to music. In 2007 Apple revolutionised the smartphone industry with the iPhone, an incredibly popular device that featured a touchscreen interface and downloadable applications, or apps. In 2010 Apple effectively kick-started the tablet industry with the iPad, a device that broke open a niche between the laptop and the smartphone.

The news comes as anticipation builds ahead of the expected launch by the company of the latest version of its incredibly popular smartphone, the iPhone. Experts have predicted the device will be unveiled on September 12th, along with a smaller version of the iPad, the iPad Mini, and a TV set.

Apple's dominance in the smartphone and tablet market has been challenged in recent years by the likes of Samsung, who Apple are currently engaged in a patent dispute with in a California court.