Most of us have been there - the dreaded customer service job. Maybe you worked in the supermarket near your house during high school. Maybe you had a job at the mall, or a diner, or McDonald's. Maybe you even did an "adult" customer service job like working in a bank. Whatever the case may be, you know about customer service - and exactly what any customer service job entails. Below, you'll find some of the many things I learned in four years of customer service. Brace yourselves.

1. You basically have to smile all the time. You smile when you greet people. You smile when you hand them their change. You smile when you mop up the tomato sauce that just splattered all over the floor. You smile when you try to explain to a customer why something they want is patently impossible. You smile when that customer tells you how utterly useless you are as a human being. Because if you aren't smiling, you're probably not being welcoming enough and the boss will notice. (You may also mutter darkly while smiling, but that depends on the job.)

2. You have had, or will have, at least one conversation with a customer that you later discuss in the break room. My first job was, of course, a supermarket job, and I can't tell you how many times somebody walked into the break room with the words "You would not believe what just happened out there!" coming out of their mouths. My personal favorite, though, has to be the one from my bank job where a customer told me I "look like I could be 18!" and, when I responded that I was in fact 18, followed it up with "Really? But you look so much younger!" (No, really. This happened.) Which brings me to the next lesson...

3. Customers say the darndest things. I've had customers ask me how much I weigh (84 pounds, and yes I know I'm underweight and I'm working on it) and how tall I am (4'11") and how to pronounce my name (yah-ELL) and whether I'm old enough to work at the bank (No, I'm not, here's your receipt). I've had a customer tell me, during the Christmas season, that I look like an elf - "You know, because you're so short." I've had a customer at the bank tell me he "hasn't seen quarters in ages." Most amusingly, between the bank and the supermarket, I've had customers respond to "How are you today?" with all of the following:

a) "Pen."

b) "Power of attorney." (Which, incidentally, she didn't have. She wanted something notarized.)

c) "Safe deposit box."

d) "Plastic."

e) "Paper."

f) "Double paper."

g) "Paper in plastic."

h) A request for directions to the other bank (which is literally visible from the teller line), and

i) a detailed description of a foot infection (right after my lunch break).

I mean, really.

4. Customers make terrible jokes and get mad when you don't laugh. "Hey, you must be making bank by working at one!" Stop. "Oh, it's not scanning? I guess it's free!" I guess you don't understand how a business operates. And of course, there's my personal favorite story, "Maybe I should cash this $150 check in pennies!" That would be 300 rolls of pennies. That's literally 15,000 pennies. Do you know how heavy that would be? Very. And hey, maybe the jokes are okay the first time. But if you are making a joke that is related to someone's job, the odds are they've already heard it. On the other hand...

5. You start being amused by things that nobody outside of your job could ever find funny. One time, I tried to explain to a customer how to make a check payable to someone else and they listened to about one third of my explanation and, as my brother described it, "Hecked it all up." If I hadn't been working in a bank, I would not have found any part of this to be amusing. Nobody who hasn't worked in a bank would find these things amusing, because the truth is they probably really aren't.

6. You lose a large amount of your optimism about people. "Parks and Recreation" fans: You know how Leslie Knope is weird because she's still optimistic about government? The same concept applies to customer service. You still like individual people, and you even enjoy some of your conversations with customers. But there's something about people as a general concept that gives you the willies.

7. You alternate between being bored out of your mind and being so busy you want to scream. I once wrote down and emailed myself a list of the random thoughts I had during a full day of work at the bank. Because of the way the printer works (slowly), I had a chance to write brief reminders of my errant thoughts, and the results were fascinating. You can actually track when the bank was busy versus when it was completely dead, because when it was busy most of my thoughts were about customers ("Five bucks says she 'didn't see me there' - yup"), and when it was quiet my thoughts were wildly varied and not entirely linear.

8. Quitting the job feels like a miracle. Finally! You're free of the hell that is a customer service job! You can regain your love of people! Or alternately, you can find a job that doesn't involve people! You can be free again! There is nothing quite like the feeling of not having to work in customer service anymore. But unfortunately...

9. It turns out that most jobs are, at heart, customer service jobs. And eventually, you learn how to take the bad with the good and only hate people in the privacy of your personal life. And hey, at least you have a surplus of customer stories.

What's your best customer service story? Let me know in the comments below!