And because the whole system can store so much information, back-up copies of everything in it can be made internally in more than one brick, meaning that such a failure destroys no data.

ECONOMIST: Data-storage systems

With 15 terabytes of hard disk storage, the Watson system at Rensselaer will store roughly the same amount of information as its Jeopardy!

ENGADGET: Watson heading to college, honing administrator-pranking algorithms

Once you have decided to purchase a gun from a retail outlet -- it could be a local gun shop or national chain such as Bass Pro Shops, Cabelas or Walmart -- the store enters your name and information into the National Instant Criminal Background Check System, or NICS, via a toll-free number or the Internet, to check the eligibility of the buyer.

CNN: Background checks on gun sales: How do they work?