gettyimages-459236718-48ccbfd9f9b0548a86b28613b0e789f261e1ec8f

gettyimages-459236718-48ccbfd9f9b0548a86b28613b0e789f261e1ec8f

Workers install a billboard for GitHub Inc. in San Francisco, California, U.S., on Tuesday, Nov. 11, 2014. GitHub, which provides open-source code hosting services and has raised more than $100 million from investors, is among tech startups boosting demand for billboard space around Silicon Valley. Photographer: David Paul Morris/Bloomberg via Getty Images