What exactly is in that backpack you wear all the time?

Interesting thread idea. I've never thought about what's in everyone's bags before, and I use a backpack constantly. It's not even a fashion choice either, more a necessity. Just a £15 Quiksilver one that I liked the look of (dark grey with orange bits.)

Anyway, on a regular day it'll contain a bottle of water, a couple of reusable plastic bags in case I need to do some shopping (the backpack itself can be used too in case I'm just buying a DVD or something.) Since I don't like to keep things in my pocket whilst I'm working I'll also put my wallet, iPod, keys and sunglasses in there.
If I'm heading to my girlfriend's after work for the night I'll also have a change of clothes for then and the next day in my bag. Plus any toiletries I need.

I don't use a backpack if I'm only out for a few hours, for example at a concert or on date night.

Very interesting. I don't think like you guys, so I never thought about it. But I gotta believe the people I'll see walking around in public with a backpack on, that's not their objective. Not that they're shady, either, I just can't see any reason for you to be walking around the mall with a backpack. Even if it did have changes of clothes, unless you got dropped off by a taxi or uber, you can leave it in the car.

I used to have a backpack or some other type of bag on me at all times. My main reason was so I could carry an umbrella because I hated getting caught in the rain yet I never paid attention to the weather forecast. As simple as that. I hated getting wet.

Edit: I should add  that I walk to as many places as I can up to two miles away.  Free exercise and good for the environment but also prime for getting caught by sudden showers.

I carry my laptop and an umbrella in mine because 9 times out of 10 when I go out I'll end up sitting in a coffee shop for an hour or so and I like having my laptop with me so I can do some work or just browse the internet. The umbrella is self explanatory seeing as I live in the UK.

Also since they charge for plastic carrier bags at stores here, if I buy anything, I just throw it in my backpack. Saves me a little bit of money and having to carry shopping bags in my hands the whole way home - it's just easier to carry in a backpack.

I bought a new one last year for travelling, taking to work and practical use. I take it into town with me so that if I'm buying stuff I can just put it in my bag to save me paying for carrier bags. It's also a godsend for going shopping for food, I used to leave the store with 3 or 4 bags that would kill my arms, with my bag I can fit most of it in there and only need to carry one or two light bags home. I'll also use it to smuggle snacks into the cinema.

I tend to bring a backpack when I go to an amusement park with my family or attend a convention. I usually carry some water,food, my portable charger, earbuds etc. And if I buy anything I rather just throw it in my backpack that way I won't have to be walking around holding it in my hand.

I don't use one. I always wear cargo shorts. It's like having a wearable diaper bag. I always carry my car keys, money clip, phone & handkerchief/bandanna. If I'm at work, just the car keys, small utility knife & a small flashlight.

I dont carry one often mostly when I go to a amusement park or a flea market. When I'm at a flea market lots of people dont have bags so its easier to carry your stuff you bought in a backpack then running it back to your car and I keep a water bottle,keys,wallet and phone in there too. Amusement park pretty much the same thing if I buy something I dont wanna carry it around the whole day or run it to the car and im keeping my phone in there too for now on since I lost my phone out of my pocket on a roller coaster twice now.

In my neck of the woods That's a sign that the person with the backpack is a drug dealer.