Proprietary: A technology belongs to one company only that company alone. All specification and documentation are hidden from the public. Unless 3rd parties that want to make use of that technology must acquire a license and pay royalties to that company. ie(Sony memory sticks, SDKs, Ports such as Apple 30-pin connector).
Open source: A documentation, technology, or specification that can be freely modified, viewed by the public for one's own benefit as well as for the community. See Linux, GNU, OSS.
Open standard: A technology, documentation, or specification that allows the general public, commercial and industrial to freely obtain and use and implement but not be necessarily free as in free beer. USB ports, Protocols, Network Interfaces, W3C, SD cards, XML, PNG, NIV Bible.
Software PATENTS: "Anyone who uses my patent must pay me royalties regardless if its an open standard, otherwise I consider it as stealing my idea".
MPEG (MP3, MPEG2, H.264, etc) = OPEN STANDARD + Full of PATENTS =