Follow the Music.

The Etune is going places.

START The digital music loop begins with tracks recorded by independent artists or record labels.

Capture Using analog-to-digital converters built into either add-in hardware or the computer itself, an analog signal is captured and formatted by a capture app, then saved to a hard disk.

Master Files stored on the hard disk are assembled by a disc-mastering app, ready to be read, reformatted, and burned to CD-R or DVD-R.

Read A desktop computer or workstation reads data from various storage formats including CDs, digital cassettes, JAZ and ZIP disks, floppy disks, or a hard disk. Once data is saved to a hard drive, it can be uploaded to the Net, or encoded using compression algorithms for distribution via streaming or downloading.

Encode A data-compression app reads the file from the hard disk, compresses the data, and saves the file to the hard disk in a new format.

File Transfer A file-transfer app connects to an FTP server via the Net, reads the file from the hard disk, and transmits it.

Serve via HTTP Having received an FTP file, a Web server saves it to the hard disk. When a browser requests the file, the server transmits it using HTTP.

Serve via Streaming When a Web browser requests a streaming audio (or video) file, a server plug-in (usually a proprietary product) transmits the file to a PC, where it's played back, or streamed, in real time.

Play Immediately As the first bytes of a streaming-media file arrive, a Web browser launches a plug-in or helper app to decode incoming data on the fly, playing it immediately until the transmission is finished.

Play After Download A nonstreaming file arrives byte by byte, accumulating in RAM until the complete file has been transferred. It can then be decoded and played by a browser plug-in or saved to the hard disk or a portable device.

Email A downloaded audio (or video) file can be attached to an email message - or, for that matter, posted to a Web site - and propagated ad infinitum, joining the Net-bound flotsam of dancing babies and trailers for Star Wars - Episode I: The Phantom Menace.

Burn A disc burner translates the data into a pattern that is burned by a laser into light-sensitive dye on the surface of a blank disc. The same deck can read the disc when it's time to rip.

THE MONEY TRAIL

Retail Sites Retailers (cdnow.com, amazon.com, samgoody.com) offer digital song files directly to customers. Record companies partner with ecommerce sites to sell music in proprietary formats or via approved third-party, copyright-friendly codecs, including Liquid Audio, a2b, or MS Audio. Playback devices are compatible with all the major codecs.

Portal Sites Portal sites (audible.com, broadcast.com, realnetworks.com) aggregate audio and video from hundreds of sources, including music, television, and film, for both downloading and streaming content. The latter is generally free, but download requires a onetime licensing fee. Watermarking helps content providers track piracy.

Hardware Manufacturers Manufacturers (Diamond, Saehan, Samsung) produce portable audio and video players that connect directly to the Net - sidestepping a PC. As bandwidth gets better and codecs improve, consumers will download full-length feature films (clickmovies.com) to home theaters, portable devices, and auto entertainment systems.

Record Company Sites Major labels (polygram.com, bmg.com, virginrecords.com) offer "memberships" - for a fee, consumers can download a fixed number of songs for playback on a PC or a portable device or to be burned onto a CD. Audio files are distributed in proprietary codecs that include watermarking to track piracy and encryption to limit the number of times a song can be copied and played.

Artist Sites Artists (beastieboys.com, aerosmith.com, therollingstones.com) sell CDs and singles as digital files directly to consumers, who can download music in several formats, including MP3, Liquid Audio, a2b, MS Audio, or G2. Copyright protections are built in with watermarking, and songs can be played on several new hardware and software devices. Customers can also listen to samples in streaming audio before buying.