A ferret is called a polecat in europe 
What type of animal is a ferret?
Its similar to a weasel its like a long furry tube cat or pole cat
Is it a rodent?
Its more in the weasel class and has black brown or white fur
How common are they?
Not very common though ferrets have thought to been domesticated for over 2500 years
Are they popular as pets?
Ferrets are domesticated polecats so they are usually pets but not the most common type of pet