This is the first of a two-part series exploring which companies are most successful in Silicon Valleys. 

In the first installment, we look at what is driving tech’s expansion into new markets. 

Next, we’ll look at the companies that are most important to the tech ecosystem and the industries that are driving it. 

The second installment will look at some of the companies who are making headlines in the Valley, like Facebook and Netflix. 

Follow the link to read Part One and Part Two. 

For more on the tech world, see Fortune’s latest coverage of the next big thing, like drones, drones for war and the next great app.

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