The 7 Must Have Items

My friend was off to Barcelona for holiday. And she's a very light traveler. Often, she doesn't bring much with her whenever she's off meeting the world. 

I remember a time, when I was off to Europe with my friends and I saw each of them was carrying at least two bags. (minimum).

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One of my friends who was flying with me spotted my luggage.
"Dude, seriously, is that it? Damn, you're very light!"

I think that's...er...a compliment?
What about you guys? What are the must-have items and accessories in your luggage that you must have with you whenever you're traveling?

If it's me, 
A.  A camera
B.  A pack of cigarette
C.  Slipper
D.  Towel.
E.  Perfume
F.  Deodorant
G.  Tooth brush

Simple. As for the clothes, at least a spare. But I don't fret much.
What about you guys? Since it's the holiday season, might as well share!