Dec 30 (Reuters) - Former world number one Tiger Woods, whose ranking has slipped to a mind-boggling 416th, celebrates his 40th birthday on Wednesday amid growing speculation over what he may yet still achieve as a competitive golfer after being blighted by injuries and poor form in recent years.
Here are key facts about Woods' life and career:
* Born in Cypress, California on Dec. 30, 1975. His full name is Eldrick Tont Woods. He was nicknamed "Tiger" after a Vietnamese soldier, a friend to his father in Vietnam.
* A child prodigy, Woods won three consecutive U.S. junior titles and three successive U.S. amateur championships before turning professional in late 1996.
* Ended that year with PGA Tour victories at the Las Vegas Invitational and Walt Disney Classic.
* Became the youngest Masters winner with a tournament record aggregate of 18-under-par 270 at Augusta National in 1997. His victory margin of 12 shots was the biggest in the tournament's history.
* After a lean spell in 1998, when he revamped his swing with coach Butch Harmon, Woods won eight titles in a golden run on the 1999 PGA tour, including his second major at the PGA Championship.
* In 2000, Woods produced one of the most successful seasons in golfing history. Romped to victory by a record 15 strokes in the U.S. Open, coasted home by eight shots in the British Open and claimed his second PGA Championship.
* Became the fifth and youngest player to win a career grand slam of all four majors and ended the year with nine titles on the PGA Tour.
* Woods won his second Masters crown in 2001 to become the first player to hold all four professional majors at the same time.
* Over the next four years, Woods piled up four more major victories and broke Greg Norman's record for most weeks as world number one with a combined tally of 332. However, his five-year reign at the top finally ended in September 2004 when Fijian Vijay Singh took over.
* In 2005, Woods won his fourth Masters title, a second British Open and reclaimed the world number one ranking in June.
* Suffered an emotional 2006, having to deal with the illness and death in May of his father Earl before winning the last two majors of the year, the British Open and PGA Championship. Ended that season with 11 titles worldwide, including six in a row on the PGA Tour.
* Clinched his fourth PGA Championship at Southern Hills in 2007 and finished second at the 2008 Masters before undergoing knee surgery two days later.
* In his first tournament after an eight-week break, Woods defied stabbing knee pain and a double stress fracture of his left tibia to win his 14th major title with a playoff victory.
* He then shut down his 2008 campaign to have reconstructive knee surgery.
* Returned to competitive golf at the WGC-Match Play Championship in Arizona in February 2009.
* Missed the cut in a major for the second time as a professional at the British Open and lost for the first time while leading a major into the final round, at the PGA Championship when he was overtaken by South Korea's Yang Yong-eun.
* In the early hours of Nov. 27, 2009, Woods was taken to hospital after he crashed his car into a fire hydrant and tree. His Swedish wife, Elin Nordegren, was reported to have smashed the car's back window with a golf club to get him out.
* On Dec. 1, he withdrew from the Chevron World Challenge, a tournament he hosts to benefit his charitable foundation, citing injuries from the crash. Media speculation began to swirl about his personal life.
* Woods said on Dec. 2 he "had let his family down" after reports of extra-marital affairs with several women emerged.
* He issued a statement on his website on Dec. 11 that he had committed infidelity and was taking an "indefinite break" from golf.
* On Feb. 19, 2010, in his first public appearance after the scandal erupted, Woods made a formal apology before a small group of reporters that was carried live on U.S. television.
* He said he had undergone 45 days of in-patient therapy for "guidance for the issues I'm facing" but did not elaborate. He said he had "a long way to go" in repairing his personal life.
* Woods returned to competitive golf at the 2010 Masters, tying for fourth, and also shared fourth place at the U.S. Open. However, he mainly struggled for form throughout the season and in November he was deposed as world number one by Britain's Lee Westwood after a five-year reign.
* On Aug. 23, 2010, Woods and his wife issued a joint statement through their lawyers saying they had divorced, and had agreed on shared parenting of their two small children.
* Won three times on the PGA Tour in 2012 and five times the following year, his victory at the 2013 WGC-Bridgestone Invitational putting him just three career wins behind the record 82 accumulated by Sam Snead.
* Injuries plagued Woods during 2014, and he was sidelined for almost four months after having a microdiscectomy surgery on his back in March. Withdrew from the final round of the WGC-Bridgestone Invitational in August after straining a different part of his back and missed the cut the following week at the PGA Championship before ending his season.
* Again struggled for form in 2015, missing three cuts in the majors while trying to cope with further injuries and the mastering of a new swing. On Sept. 16, he had a second microdiscectomy to alleviate pressure on a disc in his lower back, before needing another procedure on Oct. 28 on the same area. (Compiled by Mark Lamport-Stokes in Los Angeles; Editing by Andrew Both)