What is the hot wire in a typical 120 volt circuit

Usually the black wire is hot wire as you call it. The white is neutral and the green or bare wire is ground.

Can be any color but green, white, gray or bare.

Strat has the only correct answer.

Don't forget, it can even be white in many existing installations where cable is the wiring method, as is typical in 99% of the homes in the US.
With straight 240v circuits and 3-way switches it was not always required to re-mark the white as it is today.

There are hundreds of thousands of perfectly legal and safe 240v receptacles out there fed with "2-wire", just black, white and ground, where NO neutral is required and the black and white are used for the two hots.

The hot wire in a typical 120 volt circuit is

Travelers for 3 way and on up switches is not what I call a typical circuit.

According to the NEC all conductors have to be identified and this has been in the code almost since its inception.

Since according to statistics 73% of all electric wiring is not inspected it could be any color at any time. This is why they make meters for testing.

I wired a house where the Contractor had only seen black and white wires used. When he seen my boxes with every color available due to Travellers from multiple locations, and numerous things going on. He got mad at me and said "THOSE ARE HIGH RISE AND HIGH VOLTAGE COLORS!".
I would not say black is typical, more like it is commonly used, as is red.