Could anyone with knowledge of engines/cars/motorcycles help me out a little?
Ever since I got my motorcycle licence, people would ask me what I own, how many cylinders it had etc etc.
My answer was always: "I don't know..."
And in my head: "...and why should I care?"

So could anyone explain to me the following the layman's terms:

• What does it mean to have x-amount of cylinders.
  
• What does it mean to have x-amount of cm3 per cylinder?
  
• What does it mean to have x-amount of kW power, is this the same as horse-power but with a different unit?
  
• If kW is not HP, than what does it mean to have x-amount of HP?

And maybe the most important question, why should I know this?

I'm a bit ashamed because every driver seems to know this about his/her motorcycle, and I don't