Dependency Theory Definition

I found many definitions on what Dependency Theory was and they all seemed to have the same information and idea. The theory is about why do resources from underdeveloped countries go to wealthy countries to make the wealthy countries more wealthy. I read that the theory states that this has happened because of the exploitative nature of the third world countries to the wealthy and more powerful countries. The Dependency Theory also states that from the resources going to the wealthy countries, it is just making the third world countries more in poverty. After, reading this definition I came to realize that I guess that there is no normal distribution of anything in this world. All wealthy countries are striving to keep up with their powerful reputations and that is leaving the third world countries with no way, but to continue giving resources to the wealthy countries. It was a really interesting definition and was interesting to the read about.