A visitor has asked if their mobile gear, in particular their laptop and external USB drives can be harmed by going through airport X-ray machines. They are a frequent traveler and have concerns that over time the exposure will cause damage.
The quick answer is that no, the exposure will not damage laptops or other mobile gear that you travel with. The time that your mobile gear is actually exposed to the X-ray machine is very short.
The reason this is so is because the X-ray beam is not strong enough. It also does not emit any electromagnetic waves. There appears to be some confusion amongst travelers that the beam emitted by the airport X-ray machines is stronger and will cause damage to their laptops and other mobile gear.
If your are still concerned that your laptop or other mobile gear may suffer damage then I advise you to back up all important data to a CD or DVD, or online service so that you will have that available. It is a wise idea anyhow to create a backup of your data before traveling.