What is Economy and how it really works!

This always comes into my mind but never been able to get a wholistic picture of it and that's "Economy".  I always wonder why some countries are very rich and some other countries are dire poor. Let alone countries, a person is very rich and another person is homeless. Let me draw a picture of  an economy of the world as -

The world has limited resources
The price of an item can't be set unless it's scarce i.e. chances of not getting it is uncertain
There is more than one person who are in demand of a particular material
Not everybody is capable of doing everything i.e difference in skills and expertise


So what makes a country very rich -

A country is nothing but a bunch of people in a certain geographic area governed by a set of rules set forth by a group of people.

A country that gets more ownership of the limited resources of the world gets the higher part on the field - so it's never been a level playing field

This is bound to happen that the resources, part of the limited resources in the world, of that country is bound to be diminished in time unless the country takes up more land, which Germany had gone through that action in the WWII, or somehow creates artificial resources like iPad, iPhone, game, software etc.

!!!!!!!!!!!WORK IN PROGRESS!!!!!!!!!!!