What is an ultrabook? Which are the best ultrabooks to buy in 2011? T3 takes a look at the new generation of laptops set to be big news in 2012...

Steve Jobs got many things right, and his pronouncement this year of the dawn of the “post-PC world” had the ring of truth. The iPad and its Android tablet rivals have badly dented PC sales, which are down 15 per cent for instance in the UK in 2011, according to Gartner’s analysts. However, a new breed of laptops is fighting back, taking a hint of inspiration from… an Apple product.

To earn the "Ultrabook" title coined by Intel, ultrabooks should resemble the MacBook Air in thickness (usually at 20mm or thinner), and are designed to the chip maker’s own specification, so their Core i5 or i7 processors have an edge over the comparatively sluggish silicon in tablets.

At Computex earlier this year, Intel Executive Vice President Sean Maloney claimed, "The PC ultrabook will be 40% of the notebook market in about 18 months." With Toshiba, Asus, Lenovo and most recently HP all lining up their own takes on Intel's ingenuity, plus reports that there could be more than 50 ultrabooks shown off at CES 2012, Intel could well be right.

If you don't fancy waiting until next year to bag one, and think a leaner laptop would be the ideal Christmas gift, here's our snapshot look at the best ultrabooks to buy right now.

Asus Zenbook UX21E

Just 9mm thick at the back, slinking to a barely there 3mm at the front, the Zenbook contains Intel’s Core i5 processor, hearty speakers and an 11.6-inch screen. It’s a mouthwatering, tablet-thrashing, MacBook Air-bothering prospect.
 

Price: 1,300$, Out now

More: Asus Zenbook UX21E review

Acer Aspire S3

The 13.1-inch S3 is slimmer and lighter than the MacBook Air and packs an Intel Core i7 2637M 1.7GHz processor with 1.7 GHz clock speed. Shipping with Windows 7 Home Premium it should be the ideal pick for serious professionals.

Price: Start at 1,000$

More: Acer Aspire S3 review

Lenovo Thinkpad X1

Weighing in at a mere 1.8kg, the 13.3-inch X1 sports a backlit chiclet-style keyboard with a fingerprint scanner to log into Windows. Intel's latest Sandy Bridge processors ensures it matches performance with super-slim business looks.
 

Price: $1,199.00

Link: Lenovo

More: Lenovo Thinkpad X1 review

Samsung 9 Series notebook 900X3A

Like the Samsung Galaxy S2 is to the iPhone 4S, the 9 Series is perhaps the closest rival to the MacBook Air. Combining svelte looks with a slimline body, it also hosts an Intel Core i5 2530UM processor which combined with a 4GB of RAM gives this Ultrabook real grunt in the power department.
 

Price: 1650$ online

Link: Samsung

Toshiba Portege Z830

This weighs in at just 1.13kg and is 16mm thick. Despite that, it manages to fit a powerful quad-core Intel i7 processor, 6GB of RAM and a 128GB solid state drive into its rather businesslike-looking chassis. Tight squeeze.
 

Price: Starting 1400$, Out December

Lenovo IdeaPad U300s

This colourful number from Lenovo has a more spacious 13.3-inch screen, but still weighs only 1.32kg. Again, the solid state drive – 256GB in this case – and Core i7 processor make it a better bet than a tablet if you’re somewhat of a power user/inveterate show-off.
 

Price: $1,200. Out now

Link: Lenovo