An example of DMCA is that it is illegal to try to break the copy protection on a CD so you can make copies of it.
dmca - Computer Definition
(Digital Millennium Copyright Act) A U.S. law enacted in late 1998 that provides penalties for developing hardware or software that overrides copy protection schemes for digital media. The DMCA is considered a very controversial law by many who see it as an infringement to freedom. See copy protection.