What's so great about the Apple MacBook Air that has got the world's geeks in a lather? And why can't you add memory to Apple's ultrathin laptop? These and more of your questions are answered by our experts. Read our Apple MacBook Air review here.

When Apple's CEO Steve Jobs pulled the MacBook Air out of an interoffice memo envelope (nice touch, that) the crowd at Macworld Conference & Expo oohed and aahed. And applauded. And some even did your basic shout-out.

What got them excited was the thinnest Mac ever, and Apple's first real entry into the so-called subnotebook market. But just what is the MacBook Air?

A bunch of questions popped up almost as soon as Jobs whipped the 1.3kg, aluminium-clad MacBook Air out and held it aloft. Here are the answers.

What's the difference between the MacBook Air and the other models in the MacBook Line?

This is easy and comes down to four factors:-

  1. Price - the Air costs about £500 more than a faster MacBook when the latter is tricked out with 2GB of third-party RAM.
  2. The thickness of the case - the Air is a wood shaving compared to the MacBook.
  3. The pieces inside - the Air is missing several including an optical drive and Ethernet port but it gains others such as a multi-touch trackpad.
  4. Weight - the Air tips the scale at 1.3kg, while the similarly-sized MacBook weighs 2.3kg

Is the Air really the world's thinnest notebook, as Jobs claimed?

It appears so. Just 0.16in at its thinnest, which we assume is where Apple put the tape measure, the Air beats the minimum thickness of rivals by wide margins. The Sony Vaio TZ, for instance, is 0.8in at its thickest, while Dell's Latitude X1 is an even bulkier 1in thick. Even the AsusEee is thicker. In fact, the thickest part of the Air (near the hinge) is thinner at 0.76in than the thinnest part of the Sony, Dell or Asus models.

NEXT PAGE: the Air's processor and adding memory > >

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