1. All-or-nothing thinking - Looking at things in black-or-white categories, with no middle ground (“If I fall short of perfection, I’m a total failure.”)

2. Overgeneralization - Generalizing from a single negative experience, expecting it to hold true forever (“I can’t do anything right.”)

3. The mental filter - Ignoring positive events and focusing on the negative. Noticing the one thing that went wrong, rather than all the things that went right.

4. Diminishing the positive - Coming up with reasons why positive events don’t count (“She said she had a good time on our date, but I think she was just being nice.”)

5. Jumping to conclusions - Making negative interpretations without actual evidence. You act like a mind reader (“He must think I’m pathetic.”) or a fortune teller (“I’ll be stuck in this dead end job forever.”)

6. Emotional reasoning - Believing that the way you feel reflects reality (“I feel like such a loser. I really am no good!”)

7. ‘Shoulds’ and ‘should-nots’- Holding yourself to a strict list of what you should and shouldn’t do, and beating yourself up if you don’t live up to your rules.

8. Labeling - Labeling yourself based on mistakes and perceived shortcomings (“I’m a failure; an idiot; a loser.”)

Source: http://www.helpguide.org/mental/depression_tips.htm