The entire string of lights went out when one bulb was taken out. The rest of the lights remained lit when one bulb was taken out. Diagrams may vary, but they should look similar to the following. Diagrams may vary, but they should look similar to the following. All bulbs go out.
All bulbs go out.
The first light goes out and the second light bulb remains lit. The second light bulb goes out and the first one remains lit. There is no difference. Each time, either the other light goes out or it remains lit. If there is any break in the contact, the electrons will not be able to flow between the parts of the circuit.