Nomenclature for semi-newbie

[Chris Zacho The Wheelman]

I have a question about "types" of mountain biking and some of the words
used, like when I was shopping for tires I saw they were divided into
groups by types of riding:

Downhill, freeride, XC, racing and something called "Biker X". Racing
and downhill are pretty self explanatory. However, XC (which I assume
stands for cross country), isn't all mountain biking by definition
"cross country"? How is this designation special? what sets it apart
from other types of MTB'ing? Also, what is freeride and BikerX?

One last thing, in a book about mountain bike trails, I came across a
word they used but did not define. From it's usage, I assume it refers
to a certain type of trail hazard. All jokes aside, can anybody here
tell me what a "chicken head" is?

- -

"May you have the wind at your back.
And a really low gear for the hills!"

Chris Zacho ~ "Your Friendly Neighborhood Wheelman"

Chris'Z Corner
http://www.geocities.com/czcorner

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