Gates followed up with a couple of additional tweets, aimed at raising awareness about earthquake relief efforts in Haiti. He also admitted he's a newbie when it comes to using the site.
"Thanks to you and all the other people who have welcomed me. I've got a lot to learn about Twitter, but look forward to sharing more," Gates wrote.
In his bio section on Twitter, Gates lists his hometown as Seattle, WA and says he's interested in "Sharing cool things I'm learning through my foundation work and other interests."
Gates is co-chair of the Bill & Melinda Gates Foundation, which is dedicated to eradicating malaria and other diseases from poor countries.
Twitter is awash in fake Bill Gates pages, as well as bogus accounts for numerous other celebrities. But Gates' new page carries Twitter's "Verified Account" stamp, indicating its authenticity.
Gates is building up a fast following on Twitter. As of early Wednesday, the mogul had more than 178,000 followers. As for those he is following, Gates appears to look to a wide variety of sources for inspiration and information.
Among the 40 Twitter accounts Gates is tracking is, not surprisingly, Microsoft.
He's also following the MalariaNoMore campaign, the Carnegie Foundation, British news magazine The Economist, the European Organization for Nuclear Research (CERN), American Idol host Ryan Seacrest, the White House, Barack Obama, and UNICEF.
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