Mother Theresa once said "the poverty of being unwanted, unloved and uncared for is the greatest poverty."
At its core, those words capture what it's like to be homeless. You are a real person but in many ways, you are invisible.
Well, for the past six years, a woman in Germany has been working to change that.
Her name is Jocelyn Smith. She's originally from New York but moved to Berlin and set up 'Different Voices' - a choir for the city's homeless.
"Everyone has a voice in this choir," Smith told The Guardian. "If I can get them to sing from within, to put themselves into the notes, then I'm happy."
Smith - a soul and jazz singer - started the choir six years ago. Now, she sees a lot of regulars - 20-25 at a time - that drop in at a city community centre.
"Some people come and don't sing a note, they stand and sway or tap out the rhythm on the piano. Some sleep. But you can tell they are mostly moved by the music," she says.
Some are old, others young. Some live on the streets, others in shelters or half-way houses, and others are transients who crash with family or friends.
Together, they sing songs about whistling in the rain, being strong and staying true to your principles and values. They've even composed several numbers themselves and put on occasional concerts.
"What we all have in common is that we have very little money, no social status, no jobs, so the choir is literally the most stable thing in our lives," one woman said.
Another man said "I cried at the first rehearsal... It felt so good. Such a release, and an anchoring I hadn't felt in a long time."
Another man, well into his 60's, was separated from his brother when he was just a boy by the Berlin Wall and was only reunited last year.
He told The Guardian "The choir gives me the strength within so that I can survive the week. Even if I misbehave and have to be thrown out of the rehearsal, I know they'll always have me back."
You can read the full story here.
And Berlin isn't the only place with a homeless choir. They're starting in other major cities, including this one in London, England.
It's called The Choir With No Name. Check out this short film about it. And here's their website.