532nm is the wavelength in nanometers (532nm = Green, 405nm violet/UV BluRay, ~650nm Reds, 808nm IR/dim red visible).
But 100mW is the output power in light as measured by a Laser Power Meter (LPM). The current is expressed in mA. Voltage varies by the wavelength & temperature of the diode. And although one could use mW for the total input power (watts=volts×amps) no one ever does.
I relised that I got the mW and mA mixed up about 5 minutes ago but I was wrong on the matter anyways. I was going to say that mW would've been the power consumed via the diode. not sure if it would've still been right.
If I understand correctly, what your asking is what happens if a laser is more powerful? And what do different powers mean?
If that is what you mean? Then the greater the power, the brighter the beam will be compared to a lower powered laser of the same wavelength and it will also allow the laser to burn or melt things quicker.
Remember though that green will always be brighter than all other colours, and red and violet will always be harder to see.
You could have answered that yourself with a bit of reading,