The splitter creates a correspondence between a multi-bit value and several separate subsets of those bits. Despite its name, it can either split a multi-bit value into component parts, or it can combine component parts into a multi-bit value - or indeed it can do both at once. A more complete description of splitters is found in the `Splitters' section of the User's Guide.
Logisim treats splitters specially when propagating values within a circuit: Whereas all other components have a computed delay for purposes of simulating their behavior, values propagate through splitters (as well as wires) instantaneously.
Note: The term splitter is a non-standard term, which is unique to Logisim as far as I know. I am unaware of any standard term for such a concept; the only term I have heard used is bus ripper, but this term is unnecessarily violent for my tastes.
To distinguish the several connecting points for a splitter, we refer to the single connecting point one side as its combined end, and we refer to the multiple connecting points on the other side as its split ends.
Poke Tool Behavior
Text Tool Behavior