Most of the phones you get from your wireless service are "locked." The phone will only work on that company's voice and data network, unless you "unlock" it - a fairly simple process that enables that phone to work on other wireless networks.
Late last month, the U.S. Copyright Office and the Library of Congress announced that unlocking a cell phone violates the Digital Millennium Copyright Act - a law designed to fight digital copyright infringement.
Critics say this doesn't make sense, but unlocking your cell phone is now against the law. ABC News says those who violate the law could face civil action from their phone carrier or criminal charges if they modified phones for commercial gain.
If you want an unlocked phone, you can buy one from the major carriers - they just cost a whole lot more because you aren't locked into their service.
For example, you can get an unlocked iPhone5 from Apple and Verizon for $649.
It's Illegal to Unlock Your Cellphone