what does a 3 pole ferrite motor mean?

An electric motor has "Poles", usually 2 or 3, but sometimes more.

A motor with 3 poles is more powerful than a 2-pole motor.

"Ferrite" refers to the material the magnets are made of - In this case, they are an iron alloy

Hey MinnFlyer how come in picture two, there are two red ones and only one blue one[sm=confused.gif][sm=confused.gif]

so if the servo is 3 pole... how can you find out what the engine is..? would it have the same syncrhonous speed?

Because at that point, the two red ones are positive and the blue one is negative
The motor in the servo has nothing to do with the motor you are powering with

The wound portion of a motor constantly changes polarity so that it repels itself from the permanently poled magnets. I did a science fair project on them when I was a kid. Got an A and a blue ribbon!