The EUR/USD pair has become the most popular and the most widely used pair in the world because it represents a fusion of the two biggest economies in the world. Factors that impact the value of the Euro and or US money in relation to each other and other currencies are affected. Because of this, the interest rate differential between the European Central Bank, otherwise known as ECB, and the Federal Reserve or FED, affects the value of these currencies when related to each other. So, when the FED interferes in open market activities to make the US dollar stronger, the value of the US dollar compared to the Euro.
With that being said, bad news reports from the EU economy has a conflicting effect on prices for the EUR/USD pair. Shawn Lucas, and many others traders in the community prefer the EUR/USD pair over all other pairs and it's said that EUR/USD is way ahead of the other most traded currency pairs in terms of the daily trading volume. EUR/USD has around 50% more volume globally than both USD/JPY and GBP/USD combined. This pair is the most liquid currency pair in the Forex industry and consists of two of the most important currencies worldwide, the U.S. dollar, and the Euro.
The US dollar is the most traded and largest reserve currency in the world. It's used by other nations both officially and unofficially as their adopted currency. The Euro is the official currency of the European Union and is the second most traded and largest reserve currency in the world. The constant trading desk environment guarantees the liquidity that traders need to be able to enter and exit the market at any time.
If you’re a day trader, you want to focus on trading the Euro when there is more volatility rather than less because higher volatility will allow for your trading strategy to see its profit targets met more often. The most noticeable times of day are immediately after economic data releases and news events come out. Shawn Lucas is most comfortable when trading EUR/USD pair and you can see the results regularly. I hope you as a trader try all different pairs at all different times of the day and see what works for you as a trader.