The American writer and poet James Whitcomb Riley is credited with the observation that “when I see a bird that walks like a duck and swims like a duck and quacks like a duck, I call that bird a duck”.

The Lenovo ThinkPad x100e looks like a netbook, weighs about the same as a netbook and at $450 (￡423 in the UK) is priced (almost) like a netbook. However, in terms of performance, its speed, screen resolution and keyboard outperform netbooks. This may be why the manufacturer classifies it as a laptop, albeit a small one.

Lenovo, which acquired the ThinkPad brand from IBM five years ago, should know the difference. Its IdeaPad S10 and IdeaPad S12 machines are among the most successful netbooks, while its “T” and “X” series ThinkPads are among my favourite laptops and have helped set the benchmark for serious portable computing.