The MediaPlayer lets you play a variety of audio and video files on your computer. Its interface has standard controls, which are the same for both audio and video: play, pause, stop, fast forward, rewind, and volume. In addition, you can use the timeline sliders to set the portion of a file you want to see or hear. The MediaPlayer panel opens in its expanded state, so you can see all the available controls and access the File, View, and Settings menus; to shrink the panel, click the toggle switch at the right end of the timeline.
Select Settings > Application Preferences to open the MediaPlayer's preferences panel.
The menu choices in the expanded MediaPlayer's menu bar are also available in a context menu that pops up when you right-click on the player. In mini-MediaPlayer view, where there's no volume control slider in the window, you can get to one through the context menu: right-click to open the context menu and drag down to Volume, then grab the knob in the volume control slider that pops up to adjust the level of the file you're playing.
The MediaPlayer supports AIFF, WAV, and AU audio files, and MPEG, AVI, QuickTime, and indeo 5 video files. If you have a different type of file, go to File > Download new media add-ons in the expanded MediaPlayer panel; selecting this command takes you to a BeOS Web site where you can look for an add-on that matches your file's type.