Circuits and Switches

This week we were tasked with learning about circuits and switches. This concept came somewhat intuitively because I could visualize it. For example, when we learned in class that the rows of the breadboard are connected by conductive wire below the surface of the board but the columns are not the system of connecting elements on breadboard became much clearer.

The thing I find confusing is — what is the difference between the Volt Regulator and the Resistor? See image below for my final circuit with a switch:

Circuit using breadboard, switch made with tinfoil to be worn on fingers. Not pictured, 9 volt battery.

I know that I have a 9 volt batter, a 5 volt regulator and .7 200M ohms resistor but I don’t understand what additional thing resistor is doing if the volt regulator is there?

I decided to make a switch that could be controlled by touching my fingers together. I first checked to make sure that my circuit was working by using a pre-built switch:

I then removed the pre-built switch and made tinfoil and elctrical tape bands for my finger tips which I attached to wire (red and black) and then inserted into the breadboard.

Now the tinfoil is conducting electricity. When my fingers are apart from each other the circuit is interrupted, when my fingers are together the circuit is complete!