Email Etiquette

Whether writing a personal note or a professional response;
Keep it short and direct.
REMEMBER NOT TO USE ALL CAPS UNLES YOU WANT THE PERSON TO THINK YOU'RE YELLING AT THEM OR REALLY EXCITED ABOUT EVERYTHING!
Consider that not everyone understands "tone."
So a disclaimer: "The tone of this email is urgent, but caring..."
Helps clarify your point.
Finally, please remember that adding a period doesn't take up more time, so use punctuation, just like you were taught in school.
Thx! (Oh yes, short hand doesn't save time, it just looks foolish.)