# Glossary

Channel

  Each tab in the main window is a "channel". It represents one music directory service.

Stream

  "stream" is a technical term which means continuosly flowing data. MP3 radio music for example is streamed, because it's not just a time-limited audio file, but unending (unless you stop the player or paying your ISP).

  In streamtuner2 we also use the terms "stream" and radio "station" interchangably.

Genre

  Music genres are represented as "categories" in the left pane. Every channel groups its music stations into some structure.

URL

  URL stands for "Uniform Resource Locator" and simply means hyperlinks and web addresses like http://www.example.org/. There is also the hipster term "URI", which is technically more general (but superseeded by "IRI" and "IRL" anyway). In streamtuner2 the audio streaming link often is an URL, as is the radio station homepage of course.

Radio

  Plays music. Sometimes interrupted by advertisements.

Favicons

  Favicons are small symbols for websites. Every website has one. Or should have. As it makes it easier to associate content with homepage addresses. (ST2 downloads favicons either per menu command or automatically for the current station once you hit play.)

Cache

  Radio lists are kept in "cache" files for efficiency reasons. To not redownload stream information on every category or channel flip, streamtuner2 saves this data. This avoids time consuming server requests.

Python

  Python is a programming language. It provides extensive constructs and many functions, yet is easy to learn. See python.org and Google.

MP3

  MP3 (MPEG Layer 3) is an audio file format, part of the wider MPEG (Motion Picture Expert Group) video format. It's the most widespread format in use today, however doesn't provide the highest audio quality..

OGG Vorbis

  OGG is a multimedia file format. Vorbis is an audio compression format. OGG Vorbis was developed as alternative to MP3. It's often of higher quality at lower file sizes, and isn't encumbered by US software patents.

MIME

  For classification of web and email content, two-factor descriptions like "audio/ogg" are advised. These are called Multipurpose Internet Mail Extension types, and are used on the web in lieu of file extensions (which URL resources don't have). Note that ST2 uses the MP3 type wrong; it's officially audio/mpeg, and not audio/mp3 as shown in the settings window.

Bitrate

  Audio streams are compressed with exactness loss. This can be heard at lower "bitrates". For MP3 files any music with less than 100 kbit/s starts to hiss, while OGG Vorbis still sounds okay at a datarate of for example 64 kbit/s. So while bitrate basically means file size per duration, it's commonly used as quality indicator.

## Filetypes

Besides audio formats MP3 and OGG, there are also station/streaming link files. These are often downloaded from the directory servers, before your music player gets activated.

.M3U files — MP3-URL playlist file.
.PLS files — Playlist file format.
JSON files — JavaScript Object Notation is a common data exchange format.