Apple has announced a new version of the iMac, as was much rumoured over the past couple of weeks. Shown at the company's Special Event in San Jose, California, the new version of the desktop computer is super thin, looking much like a large iPad on a stand.

Its edge is just 5mm thick at its thinnest point, 80 per cent thinner than the current generation. The display itself is now 5mm thinner than before, and it is laminated to the front glass in order to eliminate an air-filled gap that was there previously.

One of the caveats of achieving the slimmer waistline is that the new iMac no longer sports an optical drive in its side. However, the computer components inside make it no slouch.

There are both 27-inch and 21.5-inch versions with 178-degrees viewing angles. A number of configurations will be available and start with 2.9GHz quad-core Intel i5 and 2.7GHz quad-core Intel i5 processors respectively.

Both feature 8GB of RAM and a 1TB HDD, and graphics duties are handled by Nvidia cards; the GeForce GT 640M for the 21.5-inch (with a 1920 x 1080 resolution) and the GeForce GTX 660M for the 27-inch (2560 x 1440 pixels).

One optional extra (as well as an optical drive) is Apple's new Fusion Drive, a flash memory/HDD hybrid that speeds up some usage, such as boot time and a few pre-installed apps.

As standard, Apple will pre-install its applications on the Flash drive to speed up boot times, however it will learn which apps you do use and switch them accordingly. 

The 21.5-inch iMac is available with a 2.7GHz quad-core Intel Core i5 with Turbo Boost speeds up to 3.2GHz and Nvidia GeForce GT 640M for a suggested retail price of £1,099; and with a 2.9GHz quad-core Intel Core i5 with Turbo Boost speeds up to 3.6GHz and Nvidia GeForce GT 650M for a suggested retail price of £1,249. The 21.5-inch iMac will be available in November. 

The 27-inch iMac is available with a 2.9GHz quad-core Intel Core i5 with Turbo Boost speeds up to 3.6GHz and Nvidia GeForce GTX 660M for a suggested retail price of £1,499; and with a 3.2GHz quad-core Intel Core i5 with Turbo Boost speeds up to 3.6GHz and Nvidia GeForce GTX 675MX for a suggested retail price of £1,699. The 27-inch iMac will be available in December.