A cherry microswitch is technically a single pole, double throw (momentary) switch. (SPDT)
A crude diagram is shown here:
.------------------------------------------------------------------------------------------<
v |
+ <------------- (anode) RED LED (cathode) <-------- |
--- | |
Bat | |
--- (NC)----------------| |
- --------------> (COM) Microswitch |
(NO)------> (cathode) Green LED (anode)
This diagram shows a power source (battery) connected to a cherry microswitch and 2 LED's.
If you don't press the microswitch, the RED LED will light (and the green one will not). If you press it, the GREEN one will light and the RED one will go out.
The common of the microswitch is connected to the negative of the battery, while the
NC (Normally Closed) part goes to the RED LED, and the NO (Normally Open) part goes to the GREEN LED. Both LED's are connected on their other ends to the positive terminal on the battery, thus completing the circuit.
NO means that terminal is NOT connected to the common one UNLESS you press it.
NC means that terminal IS connected to the common one UNTIL you press it.