Who is Peter Thiel and why is he advising Donald Trump?

Bosses of big US technology firms met the president-elect at Trump Tower on Wednesday. Many of the chief execs were persuaded to attend by billionaire investor Peter Thiel, who has become Mr Trump's go-to man when it comes to technology. But how did he go from tech investor to key Trump adviser?

He sits on Facebook's board and runs several firms that fund start-ups. He helped set up Paypal and is seen as one of the smartest readers of tech trends in Silicon Valley. He has the clout Trump needed to get chief executives to show up.

Not really. Official biographies do not talk about him being a precocious coder; instead he spent his time on maths and chess. He beat every other kid in California on a maths test given to high schoolers. Aged 12, he ranked seventh in the whole country in the under-13 category for chess players.

He does have some knowledge though, because in 2012 he taught an undergraduate course at Stanford about computer history and start-up advice.

It took a while. He studied philosophy and law at Stanford University and then briefly worked as a commodities lawyer. After that he traded derivatives at Credit Suisse for three years. In 1996, he quit and moved to California just as the net started its meteoric ascent.

Seeing an opportunity, he scraped together $1m and looked for ideas to invest in. Confinity, which handled net-based payments, was one of the first. It gave rise to an offshoot called Paypal, sold to eBay in 2002 for $1.5bn.

Soon after, he made another good bet by making an angel investment of $500,000 in Facebook.

Because he is a huge fan of The Lord of the Rings. So far, he has set up six firms (Palantir, Valar Ventures, Mithril Capital, Lembas LLC, Rivendell LLC and Arda Capital) that take their names from Tolkien's creation.

It's always been there. He read Ayn Rand in high school and admired Ronald Reagan at the same time. At Stanford he founded a conservative newspaper and sought work with several Supreme Court justices. Also, while a derivatives trader, he was a speechwriter for a former US secretary of education. He quit his job as a lawyer and trader because neither fulfilled his urge to make a difference - both of which could be seen as political decisions.

He has used his money for explicitly political ends. In 2012-13, he gave $10m to wrestler Hulk Hogan to help sue media news site Gawker, which had made public a sex tape involving Mr Hogan. Gawker lost the legal battle and shut down as a result. Mr Thiel is believed to have given the cash because in 2007 Gawker outed him as being gay.

It's complicated. He is apparently influenced by libertarian thinkers who favour smaller government and greater individual liberty. In a manifesto he published in 2009, he declared that freedom and democracy were incompatible.

For Mr Thiel, politics is too mired in the present to do any good. Instead, he wrote, only technology can make a difference in the world. He has backed up these words through the Thiel Foundation, which has given cash to tech firms working on breakthroughs such as extending life, living on the sea and making machines truly intelligent.

That's even more complicated. There are some clues in the speech Mr Thiel gave to the Republican Convention earlier this year. In that, he said neither he nor Donald Trump were politicians but they were both "builders" and wanted to use those skills to rebuild a "broken" America.

That speech pointed out that a lot of the money made in America over the past few decades had gone to relatively few people. The majority had seen no benefits from that wealth.

Few people were being honest about America's problems, said Mr Thiel.

But, as others have pointed out, while Mr Thiel may have put his finger on some of the issues facing America, it is not clear why he thought Donald Trump would be able to solve them.

No. Mr Thiel is believed to have become a key member of the Trump transition team. In addition, employees from Mr Thiel's venture capital fund and staff at some of the firms he founded have also been seconded to work with Mr Trump.

It is not clear what policy areas Mr Thiel and others will be advising on though it is likely to concern regulatory matters and industrial policy. As a man who has a "talent for making big, contrarian bets" it will be interesting to see how this one plays out.