The news of David Bowie's death has prompted an outpouring of tributes from his collaborators and the many musicians he influenced as well as music fans around the world and other public figures.
Bowie's life-long collaborator, producer Tony Visconti, worked with him on albums stretching from 1969's breakthrough Space Oddity to his latest LP Blackstar, which was released on Friday.
Visconti wrote on Facebook that he knew Blackstar would be Bowie's "parting gift".
"He always did what he wanted to do. And he wanted to do it his way and he wanted to do it the best way. His death was no different from his life - a work of Art.
"He made Blackstar for us, his parting gift. I knew for a year this was the way it would be. I wasn't, however, prepared for it.
"He was an extraordinary man, full of love and life. He will always be with us. For now, it is appropriate to cry."
Brian Eno worked with Bowie on albums including his legendary Berlin Trilogy in the mid-1970s. He has issued a statement paying tribute to his friend:
"David's death came as a complete surprise, as did nearly everything else about him. I feel a huge gap now.
"We knew each other for over 40 years, in a friendship that was always tinged by echoes of Pete and Dud. Over the last few years - with him living in New York and me in London - our connection was by email. We signed off with invented names: some of his were mr showbiz, milton keynes, rhoda borrocks and the duke of ear.
"About a year ago we started talking about Outside - the last album we worked on together. We both liked that album a lot and felt that it had fallen through the cracks. We talked about revisiting it, taking it somewhere new. I was looking forward to that.
"I received an email from him seven days ago. It was as funny as always, and as surreal, looping through word games and allusions and all the usual stuff we did. It ended with this sentence: 'Thank you for our good times, brian. they will never rot'. And it was signed 'Dawn'.
"I realise now he was saying goodbye."
Iggy Pop and David Bowie became good friends in the mid-1970s, relocating to Berlin together as Bowie helped write and produce Pop's first two solo albums, while Pop fed into Bowie's albums including Low. Iggy Pop tweeted:
Madonna wrote a heartfelt statement about Bowie's influence on Facebook:
"David Bowie changed the course of my life forever. I never felt like I fit in growing up in Michigan. Like an oddball or a freak. I went to see him in concert at Cobo Arena in Detroit. It was the first concert I'd ever been too. I snuck out of the house with my girlfriend wearing a cape.
"We got caught after and I was grounded for the summer. I didn't care. I already had many of his records and was so inspired by the way he played with gender confusion. Was both masculine and feminine. Funny and serious. Clever and wise. His lyrics were witty ironic and mysterious.
"At the time he was the thin white Duke and he had mime artists on stage with him and very specific choreography. And I saw how he created a persona and used different art forms within the arena of rock and Roll to create entertainment.
"I found him so inspiring and innovative. Unique and provocative. A real Genius. His music was always inspiring but seeing him live set me off on a journey that for me I hope will never end.
"His photographs are hanging all over my house today. He was so chic and beautiful and elegant. So ahead of his time.
"Thank you David Bowie. I owe you a lot. The world will miss you."
In a statement, Sir Paul McCartney said:
"Very sad news to wake up to on this raining morning. David was a great star and I treasure the moments we had together. His music played a very strong part in British musical history and I'm proud to think of the huge influence he has had on people all around the world.
"I send my deepest sympathies to his family and will always remember the great laughs we had through the years. His star will shine in the sky forever."
Fellow Beatle Ringo Starr added:
Tributes have flooded in from other many artists across the musical spectrum, demonstrating how far Bowie's influence spread.
The Rolling Stones, whose frontman Mick Jagger sang with Bowie on 1985's Dancing in the Street, sent two tweets:
Other figures from the music world paying tribute included former Soft Cell singer Marc Almond, who said: "I can't think of an artist that I've felt as much affected by, who's died. And I spent most of the morning in tears actually.
"You can't overestimate really what an enormous cultural influence he was. And for someone like me, you know, thirteen, fourteen, sort of growing up, the music world then was a very masculine world.
"And for David Bowie to come along and to have this expressive theatricality, it's was like a beacon of kind of hope and light."
Annie Lennox wrote on Facebook: "No one exists forever and it seems our elegant gentleman was well aware that his last mortal chapter was about to reach it's conclusion.
"Dark Star [sic] was his parting gift. Provocative and nightmarishly 'otherworldly'… we are jolted towards the twilight realms of epileptic seizures and voodoo scarecrows.
"The bejewelled remains of Major Tom lie dormant in a dust coated space suit… It leaves me breathless. You must see it to believe it… He knew… He could see through it all."
Ultravox's Midge Ure told BBC Radio 4's Today programme: "We all look towards what he did. We're all still walking in his slipstream. We're all still many, many yards behind what he was doing. Because he led the way. He was the leader, he was the governor.
"He was consistent in the quality of what he did. Some things he did were more commercially successful than others. But you do get the overwhelming impression that commercial success wasn't his driving force.
"Creativity was. Constantly pushing the boundaries, constantly crossing barriers, you know, invisible walls he just seemed to walk through and move into areas that no-one would expect him to do."
In a statement, Peter Gabriel said: "He meant so much to me and to so many. He was a one-off, a brilliant outlier, always exploring, challenging and inspiring anyone who wanted to push the boundaries of music, art, fashion and society.
"There are so few artists who can touch a generation as he did, we will miss him badly. Long Live Lazarus."
The Human League's Martyn Ware told BBC 5 live that Bowie was "an artist, rather than just a musician".
Ware said he didn't think his "career would have happened at all, were it not for David Bowie", adding: "It wasn't just about the music he made, it was about fashion, it was about - he lived his life as though he were an art installation."
And Glastonbury Festival founder Michael Eavis recalled Bowie's first appearance at the event. "He came in '71 with lovely, long flowing hair like a hippie, he was fantastically beautiful and nobody knew who he was," Eavis said.
"He played at four in the morning at sunrise, songs that we'd never heard before and it was great fun. He's one of the three greatest, there is Frank Sinatra, Elvis Presley and David Bowie. I was only half awake because I'd been up all night."
Bowie's influence spread beyond the music world, as UK Prime Minister David Cameron has attested. Mr Cameron recently picked Hunky Dory as his favourite album.
"Today we are mourning the loss of an immense British talent," he said. "Genius is an over-used word but I think musically, creatively, artistically David Bowie was a genius.
"For someone of my age he provided a lot of the soundtrack of our lives, from the first time I heard Space Oddity to watching our athletes appear in those wonderful Olympics to the strains of Heroes.
"He was a master of reinvention and one of the things that is so incredible is almost all his reinventions were incredible successes and worked brilliantly. So, we mourn the loss of a great talent. We think about his family and friends, who have lost a loved one too early, but I think also we celebrate an immense British talent who has enriched all of our lives."
Labour leader Jeremy Corbyn told the BBC Radio 4 Today programme that Bowie was a "great musician, great entertainer".
"As soon as I heard of his death, very, very sad, Life On Mars comes flowing back into my mind. Wonderful song, wonderful guy," he said.
The Archbishop of Canterbury Justin Welby also gave his reaction to the star's death, speaking to BBC Radio 4's Today programme.
He said: "I'm very very saddened to hear of his death. I remember sitting and listening to his songs endlessly in the '70s particularly, and always really relishing what he was, what he did, the impact he had."
And the Vatican's chief spokesman on cultural matters, Cardinal Gianfranco Ravasi, tweeted the lyrics to Space Oddity:
Two current star men have also paid tribute. British astronaut Tim Peake sent a tweet from the International Space Station.
And fellow astronaut Chris Hadfield, who famously sang Space Oddity in space, tweeted: