Here are the terms to look for when you're reading up on a company's support options.
Warranty: A warranty is a company's guarantee that the product you've purchased is in working order and doesn't have any known defects. It also guarantees that the vendor will repair or replace defective parts, without charge, within a specified time. Often, a vendor will attach some conditions to this policy to protect against paying to repair a defect that you, the consumer, have caused.
Unlimited warranty: An unlimited warranty guarantees free replacement or repair of any defective parts, usually within a specified period of time (such as one, two, or three years or, possibly, the lifetime of the product).
Limited warranty: A limited warranty replaces only some, not all, defective parts within a specified period of time. Parts that are subject to free repair should be spelled out in a warranty agreement, which should be available on a vendor's Web site. Note: Limited warranties may also restrict repairs, depending on how the damage was caused.
Onsite service: Onsite service means that a company will send someone to fix your PC or notebook (or other equipment) wherever it is located.
Return to depot: This type of warranty coverage requires you to send a defective or broken product back to the company for repair. Some companies cover shipping costs, but others do not.