What is an exchange rate?

Overview
In this discussion topic, we will be discussing exchange rates.
Instructions
In your post, address the following questions:
What is an exchange rate? What is the exchange rate currently for the US dollar and the euro? for the dollar and the yen? for any other currency of your choice?
Where appropriate, cite examples from your text or other readings.
Rubric says:
Post includes substantial and thoughtful content with appropriate terms and concepts learned in the course utilized. Post addresses fully the topic question.
References cited as needed.