There are 156 million emails sent per minute, according to the World Economic Forum. We rely on email for both personal and professional communication — and if we aren’t careful, a poorly-written email could wreak havoc on both. However, as important as email is to our lives, knowing the proper etiquette for email correspondence is tricky, since finding a hard and fast rulebook is somewhat nonexistent. Just like communication over the phone and in-person, it’s essential to express yourself in…