What is "Phantom Power" ?

"Phantom Power" is a feature on some desks and amplifiers that enables the use of condenser microphones.
Condenser microphones need 48volts (sometimes less) to operate, and "phantom power" supplies this.
If you don't have condenser mics, you don't need phantom power.
Conversely, if you don't have phantom power, your condenser mic won't work. (unless the mic is battery operated of course - but that's another story....)