Currency wars

This will be a quick post but I wanted to bring up something I found while researching economics. Its an issue that has grown since the expansion of international trade. Especially with the rapid connections in communication. Its called currency wars. Basically it has to do with the change in value of a country's money in relation to that of other countries. What I didn't realize is that some countries could actually benefit from lowering the value of their currency. Check out this video to learn a little more. Also this article I found talks about currency purchases and why this might not be viable today. I'd also be interested  if anyone has any more good sources on this topic.