People with depression are opening up about the invisible side to the mental illness, in a bid to show that you can't "see" the inner struggles they are dealing with on a daily basis.
The #WhatYouDontSee campaign was launched by The Blurt Foundation to coincide with Depression Awareness Week.
It has inspired a wave of people to open up about their insights and experiences of depression and other mental health issues.
"We want to highlight the reality of depression, the impact depression has had on our lives, giving people a chance to share ‘what you don’t see’," reads Blurt's website.
Jayne Hardy, founder of The Blurt Foundation, told The Huffington Post that the campaign comes as a response to people who have told someone with depression that they "don't look depressed".
"Again and again, members of our community tell us they’ve been told they don’t ‘look depressed’, that they can’t be ill because they’ve been spotted smiling, that they’re too young/old/pretty/smiley/privileged to be depressed, and so on," she explained.
"We’re so over hearing comments like this. Depression can hit anyone, at any time, regardless of age, gender, and personal circumstance.
"You can’t tell from the outside who is suffering, because depression can’t be seen."
The #WhatYouDontSee campaign encourages people to share ‘mhelfies’ – pictures of themselves, as someone affected by mental health issues – with a caption explaining what others can’t see.
Those who don't want to share a selfie can simply tweet their feelings using the hashtag.
Here are just some of the tweets that have been shared so far...