Laptops and netbooks are great devices, they provide us with portability, we can take them anywhere and work conveniently with them, well, in our laps. Due to their small size there are some inherent problems, the biggest enemy of a laptop is heat. The components are very similar to the ones in your large desktop PC just smaller, sometimes modified to generate less heat.
Be aware of your cooling vents!
If you operate your laptop on a soft surface like your lap be mindful of where the ventilation ports are. The air that cools a lot of the most critical components needs to enter through the bottom of the laptop. Check out the vents on this Sony Vaio netbook:
Above: You’ll note that it is extremely easy to block the vents on this Sony Vaio Netbook. Below: Here is a laptop – a Lenovo W510:
The Lenovo has much better distribution but it is still possible to block them all if you lay it on a soft surface. It is always best to lay laptops on hard surfaces whenever possible. That allows them to breath fresh cooling air through the bottom and allows the large side exhaust vents (not pictured) to properly eject the hot air from your expensive and useful laptop or netbook PC. You can keep those vents free using a little blast of canned air when you notice dust accumulating.
My Very Biased Opinion:
We are a Lenovo Partner and we recommend and sell their products. With 13+ years in the business I can say with great confidence that Lenovo Thinkpads are the best in the business. If you really want your laptop to last, buy a Thinkpad. While preparing this article I was greatly surprised by the contrast in the ventilation on all the laptops I looked it while making preparations.