Have you been hearing beeps from your PC, and wondering what they mean?
Those beeps come from your machine's BIOS (a little piece of software built into the motherboard), and they're its R2-D2-esque way of communicating with you. "Beep codes" vary a bit from BIOS to BIOS, but in general one quick beep means that everything is working fine. If you hear two long beeps followed by three short ones, that could mean that the system failed its keyboard-controller interface test (one of many that run during a typical PC boot). One long followed by two shorts usually points to some kind of video failure. And so on.
If you hear anything other than a single happy startup beep, check your system manual, which should list the various beep codes. Failing that, an Internet search from a PC that isn't beeping cryptically should produce the information you need, though most listings are divided by BIOS manufacturer (AMI, Award, and the like). To learn who made yours, check your manual, call the seller of the PC, or carefully pop the hood (if it's a desktop) and try a visual inspection: Most BIOS chips have the manufacturer's name printed clearly on top. Figuring out what BIOS beeps mean can greatly assist your troubleshooting efforts.
(For more solutions to perplexing PC problems, see "The 21 Greatest PC Mysteries--Solved!")