PitchBook has ranked the top startup cities in the world, with San Francisco, New York, and Beijing topping the list.

Among the essential components propelling a startup ecosystem are a vastly interconnected network of IT talent, venture capital firms, and entrepreneurs.

These tech clusters are expanding globally as growth engines. Although America is home to the majority of the world's top startup towns, other ecosystems, like Beijing and Seoul, are becoming more well-known as nation...