This emitter simulates a continuous stream of liquid, such as can be used for a running tap or the upper edge of a waterfall. The advantage over the comparable Basic Emitter is that all settings for the properties of the liquid can be set directly on the emitter without having to convert a standard particle flow via a Liquify Modifier. This also enables more natural fluid simulations right from the start, as initial overlaps of the particle radii can be avoided directly during emission.
In this respect, there are also parallels to the Liquid Fill Emitter, which also works with a regular particle structure that is advantageous for liquids.