I'm currently sorting my electronics, but I'm not sure if a voltage regulator is an IC. I can't seem to find any information and I am struggling to understand whether certain components are ICs or not.
I am not going into the discussion at what point a circuit is complex enough to be called an integrated circuit.
I can imagine that a voltage regulator looks so simple (just three wires) that it is difficult to see why it would be called an IC. Not much different from transistor: it has about the same size and same number of connections!
So I looked on the WWW a for diagram of what is inside an LM317 and a 7805. Two very common voltage regulators. This gives a better notion of the complexity of those circuits.
'Integrated circuit' means just that: a circuit, integrated onto one piece of silicon.
An electronic circuit is an arrangement of connected components that perform a useful function or task.
Here, integration means to combine things into a single useful thing.
Hopefully this will show you the clear distinction between a single silicon component and an integrated circuit.