D-STAR technology explained by Wikipedia
D-STAR (Digital Smart Technologies for Amateur Radio) is a digital voice and data protocol specification developed as the result of research by the Japan Amateur Radio League to investigate digital technologies for amateur radio. While there are other digital on-air technologies being used by amateurs that have come from other services, D-Star is one of the first on-air standards to be widely deployed and sold by a major radio manufacturer that is designed specifically for amateur service use.
D-Star compatible radios are available on VHF and UHF and microwave amateur radio bands. In addition to the over-the-air protocol, D-Star also provides specifications for network connectivity, enabling D-Star radios to be connected to the Internet or other networks and provisions for routing data streams of voice or packet data via amateur radio callsigns.
The first manufacturer to offer D-Star compatible radios is Icom, and no other amateur radio equipment manufacturer has chosen to include D-Star technology in their radios, yet. Kenwood re-brands an Icom radio and distributes it in Japan only. [...]
You can read the whole thing for more information about the history and technical details. For a glimpse of it's more practical applications, have a look at Icom's website, which gives a description of the practical uses of the technology:
With Digital Voice & High Speed Data
What is D-STAR?
D-STAR is a new ham radio system which offers digital voice and data communication. It connects repeater sites over microwave links and the Internet and forms a wide area ham radio network. The DSTAR system provides a new capability and functionality to the ham radio world and increases the efficiency of emergency communications.
What can the D-STAR system do?
128kbps digital data and 4.8kbps digital voice communication
The D-STAR system provides not only digital voice (DV mode) communication but also digital data transmission (DD mode). It can exchange various data files such as graphics, images, etc, at 128kbps.
Your voice and data can reach further than ever
Multiple repeater links by radio and the Internet provide long distance communication to virtually anywhere.
Internet application available
The D-STAR system uses the TCP/IP protocol, so when connected with a PC, web, e-mail and other Internet applications are available.
Wireless Internet Access
No matter where you travel within the DSTAR network, you can access the web, e-mail, text messages and multimedia messages.
In DD mode, ID-1 can transfer data directly with another ID-1 without the use of a repeater. This is useful for establishing a simple network where a D-STAR repeater does not exist or D-STAR services are not required.
Increase efficiency of emergency communications
Out in the field, fast emergency information is the key. Send pictures and weather charts to or from a remote location with the ID-1. “A picture is worth a thousand words”, and efficient send/receive opens up your repeater for other emergency communications. [...]
There's more about the features -LOTS more- but the more I read about it, the more I see that the technical aspects go over my head. I'm a total newbie to HAM radio, and I think before I can learn much more about D-Star, I'll have to learn more about HAM radio first. Here is a video on Youtube, that is a basic introduction to D-Star and some of the things it can do:
For anyone with more questions about D-Star, there is a D-Star forum where you can ask your questions. I think it's a fascinating convergence of two technologies, and I will be watching it's progress with great interest.