Apple boss Steve Jobs has unveiled the world's thinnest laptop, called the MacBook Air.

The computer, which is 0.76 inches (1.93cm) at its thickest point, was unveiled at an event in San Francisco.

The Apple head also launched online film rentals for iTunes users in the US from almost every major film studio, including Disney and Fox.

"We're dying to get this international as well," said Mr Jobs, saying it would roll-out worldwide later in the year.

Of the laptop, Mr Jobs said: "It's an amazing feat of engineering."

It does not have a CD or DVD drive in order to save space. "It was built to be a wireless machine," he added.

The laptop will compete with a range of portable devices, from companies such as Sony, Dell and Asus, which are already building so-called sub-notebooks, designed to be lighter and more mobile.

The machine goes on sale in two weeks and costs from $1,799 in the US (£1,199 in the UK) and comes with either an 80 Gigabyte hard disc drive as standard or 64 Gigabyte solid state drive for an added $999.

Apple worked with chip maker Intel to produce a smaller version of its Core2Duo processor for the laptop.

Movie rentals from the key Hollywood movie studios will be available in the US immediately. Until now customers have had to buy movies outright but now they rent them for up to 30 days, or for 24 hours once viewing has started.

Movie lovers will be able to download films to their computers, and transfer them to the latest iPods and iPhone, in standard and high-definition, for between $3 and $5.

The company also announced it was revamping the Apple TV device so that it can now download content independently of a computer and display it on a widescreen TV.

Mr Jobs admitted that Apple's first attempt to put online video in the living room had failed.

"[Apple TV] was designed to be an accessory for iTunes and your computer.

"It is not what people wanted. What people really wanted was movies, movies, movies."

He added: "We weren't delivering that. We're back: With Apple TV Take Two."

He announced the firm had sold 125 million TV shows and seven million movies via iTunes.

"It's more than everyone else put together, but it didn't meet our expectations," said Mr Jobs. "I think we've got it right this time."

Mr Jobs also announced a wireless back-up system called Time Capsule, offering a combined wi-fi router and hard drive.

New software for the iPhone was unveiled, including an update to Maps, which can plot the phone owner's spot on a map without using GPS.

Apple announced it had sold four million iPhones in the first 200 days on sale, putting it on target to sell 10 million by the end of 2008.