Are Cycloalkanes Aliphatic

It says in my book that

Aliphatic - no ring structure

But Cycloalkanes have a ring like structure

And this asks:
"C5H6 (Cyclopentane) - Why is it aliphatic and not aromatic?

A saturated ring is an ALICYCLIC structure,
To make a long story short, aromatic structures are rings with conjugated double bonds in the ring. Benzene, etc are aromatic.
(Cyclopentane is not aromatic, neither is cyclopentadiene. But the cyclopentadiene ANION is!! But that's week 2 or 3 or the aromaticity lectures.)

Since cylcoalkanes do have at least one ring structure, they are not aliphatic. However, they have similar chemical properties to alkanes, especially those with five or more carbons in their rings. Cyclopropane and cyclobutane have strained carbon-carbon bonds.

Cylcoalkanes, such as C5H10, cyclopentane are saturated and not aromatic hydrocarbons. Aromatic hydrocarbons have conjugated double bonds in their rings and are stabilized by resonance.
http://en.wikipedia.org/wiki/Resonance_%…