Question

How to bring someone out of depression?

Answer 1

consult a psychologist. Therapies might be needed. Time to time appointment with psychologist will also help

Answer 2

Well, depression in this generation is something really common. As we grow and develop more, the more diseases and disorders spread. 

This is getting common, but we never learn. 
What causes depression?
Overthinking. Humans think too much, the complexity of their thoughts are powerful enough to destroy the whole Earth together, but instead of using it for benefitting the only living race known in the Universe, thoughts have been used as a weapon against our own selves. The more we think, the more matters become worse.

A simple matter can be tangled by thinking too much, and to eradicate depression, stop thinking. If you think and stress about something from the past. Scars are not something that denote your weaknesses, they are something that show how brave you were during war.

Try to move over with it. Try new activities and explore life, you will have more fun trying out new things and learning more. 

Read novels. Books cover a huge expanse of emotions and knowledge. Reading a single book can take you places beyond the Solar System. They teach you new lessons, and can totally change your way of thinking. 

Try helping out others, seeing others happy will make you happy. 

Cheer them up! Divert their minds. Human minds are really complicated, so if your friend is depressed, don't try to talk about it. Divert the topic, and go off the road. Try being with them as much as possible, even if they kick you off, but don't annoy them! Show them that you care, and they don't have to be alone : )

If it doesn't work out, take them to a friendly consultant, don't rush to doctors, seeing hospitals or consultors will scare and surprise them, which is what you don't want. Take things with patient, and stay positive : )