Feeling depressed and having depression are two very different conditions that people often tend to conflate.

This video by TED-Ed explains what separates clinical depression, "the leading cause of disability in the world", from the state of feeling low or sad, like when we have an argument or are unwell. 

Clinical depression is a medical disorder which affects the way we feel, think, talk or act. 

And it comes with a host of symptoms including not only behavioural changes but also physical manifestations inside the brain. 

There are several effective treatments for depression, including medication and therapy, and scientists are working on developing newer ones.

The video also attempts to explain what exactly causes depression along with a guideline on what to say and what not to say to people suffering from the condition. 

Watch the video to know more: