Let's see if my memory serves me correctly.
First off, the term Left and Right came from olden monarch days. Some state it mainly manifested during the French revolution, but who knows for sure. The basic premise to the original definition is this. The king had a set of consulars he used to help him rule his country. He stacked on his tables those with a conservative ideology to his right, and those with a liberal ideology to his left.
The conservatives basically like minimal change to the way government ran anything. Be it good or bad, the conservatives found nothing inherently wrong with the system as a whole and only small tweaks should ever be made.
The liberals liked to change things if they thought it would make things better. That doesn't mean increase in government, but just change. Maybe a tweak to the tax code here or there. Basically any government ruling function that they thought required change they wanted to implement.
That's the basics of the origins of the two parties. One for change, and one for staying the same.
However, there are certain groups that typically favor one form of government style over another for various reasons. You'll also find that those on the Left can shift quickly to the Right once their changes they wanted are made and done. For example, if the current government had very little in the way of civil liberties for certain classes of people, then the politician that would speak for government changes to bring about more civil liberties for those would be considered on the Left. However, if those changes were implemented, if the politician was happy and wanted nothing else changed in the government then he/she would shift to the Right. Vice versa as well.
Left = wanting to change something
Right = wanting to change nothing
This bullshit Texashiker is posting about communism, anarchy, fascists, socialists, centrists, and blah blah blah are different political parties that either had right or left leaning ideas based upon the current government.
Communism for example would be VERY left leaning in the USA because it would be a MASSIVE change to the current setup. That doesn't mean every "left" leaning person would be wanting to implement communism. That's stupid to make that equation. Now in a country like China, the communism part would NOT be the Left wing side. It would be the ultra Right wing side. Why? Cause China does not want to change it's current government structure based upon communism.
People forget the basics. It's simple as the equation I put above.
So where do "central" people fall if left means change, and right means no change? In reality there is no on truly central. They may like less change than the far Left, and no change on some government issues. Usually they are the ones that like compromises in terms of changes. Maybe something that someone on the far left things of as a HUGE change needed to be done, the centralist will think only a compromised small change is needed instead.