A splitter splits a single AV signal into several signals. Think, for example, of splitting a digital optical signal with an optical splitter. With an audio splitter, you can make multiple audio inputs from one audio output so you can listen to music from the same device via multiple headphones, for example. An HDMI splitter ensures that you can split the signal from one device, such as a Blu-ray player or game console, into multiple signals and view them on multiple screens.