I arrived at the Internapalooza in San Francisco last month with no idea what a “palooza” actually was. Wading into a throng of excited backpack-clad computer-science students all filming on their iPhones, I got my first taste: a cross between Black Friday and an X Factor audition.

Tech-company interns attend this annual event, held in the city’s baseball stadium, ostensibly to hear esteemed speakers and make contacts. It is organised by Cory Levy, co-founder of teen social network After School, and attended by interns from Google, Facebook, Salesforce and more.

The interns come for free, while companies pay, setting out their stalls in the hope of recruiting these bright young things when they graduate. “We bring together the smartest kids in Silicon Valley, who go to school across North America, and magical things happen,” Levy said.