A lot of EASA standards, such as maintenance, have been directly drawn from the FAA.
Although sneered upon by many in Europe, with regards to training, the FAA system is much more straightforward and practical and, when it works as intended, works very well, but it is open to abuse. They know that you will get training throughout your career and, in practice, the insurance companies won't let you fly until you get it.
EASA, on the other hand, does not assume that and requires you to know everything before you start, which is why there are a lot of questions in the exams that may not seem relevant. There is also hardly any standardisation between examiners, whereas, in a place like Canada, you will get the same ride everywhere you go - I presume it is the same for the US as the systems are similar.
The legal system is different, as well - in Europe, you need to be granted permission specifically to do things. This causes a conflict in somewhere like UK where you can do what you want unless there is a law against it.
That's a start, anyway.
Phil