Tributes have been paid from around the world to Olivia Newton-John, who has died from cancer aged 73.
The British-born Australian singer and actress was best known for playing Sandy in Grease, one of the most successful film musicals ever made.
Her Grease co-star John Travolta said she "made all of our lives so much better" while its director said: "What you see is what you get with her."
She died peacefully at her California ranch surrounded by family and friends.
An actress and musician, Newton-John achieved commercial success as a country singer and sold millions of records globally.
But it was her role as high school student Sandy in the film Grease that catapulted her to worldwide fame.
The musical was the biggest box-office hit of 1978, and gave Newton-John three huge hit singles, including You're The One That I Want and Summer Nights, both performed with co-star John Travolta.
And it was a catalyst for change in both her image and her musical direction - shedding her innocent, country-pop image.
Following the news of her death, scores of fans as well as famous figures from the world of entertainment began to share heartfelt messages and memories.
Singer Rod Stewart called her "the perfect lady, gorgeous, with great poise and with a certain Aussie sophistication".
US television host Oprah Winfrey said her "positivity was just infectious". "You'll be missed, Olivia," she wrote. "Here's to the good times."
Travolta wrote on Instagram: "Your impact was incredible. I love you so much. We will see you down the road and we will all be together again."
"Yours from the first moment I saw you and forever!" he added, signing off: "Your Danny, your John!"
Newton-John was first diagnosed with cancer in 1992 and went on to become a leading advocate for cancer research. Her charity, the Olivia Newton John Foundation, has raised millions of pounds to support research.
In later years, Newton-John became a cancer campaigner which led to the opening of an institute named after her in Melbourne
Newton-John was born in Cambridge, UK on 26 September 1948.
Her father had been a British spy during World War Two. Her mother was the daughter of the German Nobel laureate, Max Born, and had fled with her family when the Nazis came to power in 1933.
The family moved to Australia in 1954, where she was raised.
Her breakthrough came in 1971 when she released a Bob Dylan-penned track, If Not For You, which reached number seven in the UK charts and featured on an album of the same name.
She won four Grammy awards and scored seven US number one hits between 1974 and 1977.
In 1978 she became a global star with the release of Grease. The film, set in the 1950s, told the story of Sandy's summer fling with John Travolta's Danny and the difficulties the relationship encounters. In the end the pair reconciles with Sandy having transformed her appearance.
The British-born Australian singer and actress was best known for playing Sandy in Grease, one of the most successful film musicals ever made.
Her Grease co-star John Travolta said she "made all of our lives so much better" while its director said: "What you see is what you get with her."
She died peacefully at her California ranch surrounded by family and friends.
An actress and musician, Newton-John achieved commercial success as a country singer and sold millions of records globally.
But it was her role as high school student Sandy in the film Grease that catapulted her to worldwide fame.
The musical was the biggest box-office hit of 1978, and gave Newton-John three huge hit singles, including You're The One That I Want and Summer Nights, both performed with co-star John Travolta.
And it was a catalyst for change in both her image and her musical direction - shedding her innocent, country-pop image.
Following the news of her death, scores of fans as well as famous figures from the world of entertainment began to share heartfelt messages and memories.
Singer Rod Stewart called her "the perfect lady, gorgeous, with great poise and with a certain Aussie sophistication".
US television host Oprah Winfrey said her "positivity was just infectious". "You'll be missed, Olivia," she wrote. "Here's to the good times."
Travolta wrote on Instagram: "Your impact was incredible. I love you so much. We will see you down the road and we will all be together again."
"Yours from the first moment I saw you and forever!" he added, signing off: "Your Danny, your John!"
Newton-John was first diagnosed with cancer in 1992 and went on to become a leading advocate for cancer research. Her charity, the Olivia Newton John Foundation, has raised millions of pounds to support research.
In later years, Newton-John became a cancer campaigner which led to the opening of an institute named after her in Melbourne
Newton-John was born in Cambridge, UK on 26 September 1948.
Her father had been a British spy during World War Two. Her mother was the daughter of the German Nobel laureate, Max Born, and had fled with her family when the Nazis came to power in 1933.
The family moved to Australia in 1954, where she was raised.
Her breakthrough came in 1971 when she released a Bob Dylan-penned track, If Not For You, which reached number seven in the UK charts and featured on an album of the same name.
She won four Grammy awards and scored seven US number one hits between 1974 and 1977.
In 1978 she became a global star with the release of Grease. The film, set in the 1950s, told the story of Sandy's summer fling with John Travolta's Danny and the difficulties the relationship encounters. In the end the pair reconciles with Sandy having transformed her appearance.
