Yes, there are many different styles of handlebars with different designs.

Tire characteristics also include adhesion to the road and comfort of ride.

Float is the amount of sideways (horizontal) movement allowed usually expressed in degrees.

You do not adjust the chain, you adjust derailleurs. Assuming the chain is sized properly you monitor it for wear. When a chain is worn, commonly referred to as stretch which is not stretch at all but the chain links reducing in size from wear, you replace it.

Roadbikereview.com has a beginner's forum where you are guaranteed not to be flamed for asking such basic questions. You will probably get much more knowledgeable answers here but will also get flamed. Such is life.