1. The graduated frat boy/sorority girl.

When this professor winks “have a good weekend” at you, you can tell they’ve been around the block a few times. Often this professor acts more like a friend than a teacher.

2. The professor who doesn’t care.

You can turn in your assignment, or not. This professor doesn’t really care. He probably doesn’t even read your papers. He gives everyone a solid B+ and thinks no one notices.

3. The HARD ASS who really isn’t a hard ass.

This professor thinks he makes his students rue the day they were born, when in actuality his class is a breeze.

4. The ACTUAL HARD ASS.

This professor makes his students rue the day they were born. He’s the type who will re-correct your quiz and make you lose points, not gain them. Sometimes this teaching style is effective but only when you’re….

5. The passionate hard ass.

This is the professor who makes it impossible to get even a B, but when you do, it feels amazing just to have impressed someone with such high standards.

6. The favorites-picker.

If you are one of her two or three favorite students, this professor will make you feel as good as Kanye West every day in class. If you’re any of the others, though, you’ll spend those dreaded sessions rolling your eyes at every word one of the “favorites” chirps.

7. The language barrier.

As much as you know this professor is passionate about his or her work, you just can’t understand a word they’re saying.

8. The technologically challenged.

You bite your tongue as this professor tries to locate the “present” button on Microsoft Powerpoint or wonders why “those damned speakers are broken!” when the Youtube video is on mute.

9. The lives in his/her office.

If you have any questions for this professor, you’re in luck. They never leave their office. Ever.

10. The shows up 14 minutes late.

You know that whole, “class is cancelled if the professor doesn’t show up after 15 minutes” rule? This professor kills that dream time after time that she shows up after 14 minutes.

11. The just out of college.

You’re 90 percent sure you saw this professor out at the bar last night. Knowing she looks like a student, this professor tries desperately to be taken seriously.

12. The professor you want to be when you grow up.

This professor is lovely in every way. She shares stories of her life that make you want her to adopt you. Also probably has a cute dog.

13. The researcher.

Unfortunately, this professor is not a professor because he strives to mold young minds for the better. Instead, he keeps the gig just so someone will fund his research.

14. The I see what you're doing there but...

This professor does not hesitate to tell you your opinion is the wrong one, even on something that is completely subjective.

15. The dad joke professor.

Let’s face it, his jokes aren’t the funniest. But he’s a lovable guy so you push out a couple of “ha ha”s to appease him as he tries to make Calc funny.

16. The professor who changes your life.

She makes you see the world in a completely different light, someone you will never forget.