She has yet to get her driver's licence, but New Zealand golfer Lydia Ko, 17, has replaced Tiger Woods as the youngest golfer ever to reach world No. 1.
Woods, who topped the rankings at age 21, has held that record since 1997.
"To have that honour by my name, I can't believe it. Tiger Woods, he's amazing," she said when told on Sunday.
Here's more about the precocious golfer:
1. Brilliant student
Ko was born on Jeju Island in South Korea, but emigrated to New Zealand at a young age. She is still enrolled as a student at Pinehurst School in New Zealand, and teachers say she was handing in school projects even while on tour.
"She is one of the most level-headed girls you'll ever come across," a teacher told Sports Inc TV.
Classmates said she excels in her studies, and the all-rounder will study psychology at Korea University in Seoul from this year.
2. Golf prodigy
Ko started playing golf at five and competed in New Zealand's women's national amateur championships at seven.
"She skipped down the Titirangi fairways," said the 2005 article in the New Zealand Herald that first mentions her.
A decade on, she is world No. 1, was the youngest-ever LGPA rookie of the year, and is the youngest millionaire in LPGA history. Ko, then 16, was given a special exemption in October 2013 to join the LPGA, which has a minimum age of 18.
She was also named one of Time magazine's 100 most influential people in 2014.
Annika Sorenstam, an eight-time LPGA player of the year said in the Time feature: "Lydia Ko is exceptionally talented, mature beyond her years and well liked by golf fans and competitors alike. She is responsible for sparking increased interest in our sport not just in her native South Korea and adopted homeland of New Zealand but also among juniors across the globe."
3. Family support
Ko's mother Tina Hyon is present at every round, training session, and tournament her daughter plays.
"I'm enjoying it," she told Stuff.co.nz "It's important for me to be there for Lydia - she's still very young... We're staying in an apartment close by, so I can cook for her and (make it less) stressful for her when she plays."
Her father, Ko Hong, has been her caddie and has bought a house in Florida where she will be based as a professional golfer.
4. Just another teenage girl?
Not really, but like other girls her age, she likes Lady Gaga, Lorde and One Direction - and pizza. She reads teen fantasy novels like Mortal Instruments, and likes action movies.
Like you, she watches Korean dramas. She also loves karaoke, according to her website. But there is little time for that, as she is apparently training five or even six days a week.
5. 'Great personality'
The consensus is that Ko is down to earth and serious about her sport, but also fun to hang out with. She handles the media with aplomb, and impresses her competitors with her maturity.
Golfer Christina Kim, who played with Ko, told Stuff.co.nz she is "funny as hell". Coach David Leadbetter says she is always cracking jokes, and that she has a "great personality".
Instead of calling a press conference to announce that she was turning pro in 2013, she made a funny video.
