Over the past few years, a new technology-driven entrepreneurial boom has exploded in and around San Francisco. Thousands of ambitious companies are emerging, bootstrapped and often with just a few employees at first, to challenge business as usual in industry after industry, from food to health care to education to media and beyond.

Collectively, these startups have the potential to transform the way we live our lives.

This boom doesn't really have a name. But it is centered around the convergence of several different technological trends, including social media, location-based technologies, and mobile devices like tablets and smartphones. It also has a lot to do with data—collecting, sifting, and interpreting data about how all of us use the new technologies we are increasingly dependent on.

That this boom without a name is occurring during a severe economic recession has a certain irony. Could it help generate new jobs, especially for those whose industries and professions have been so badly disrupted?

Well, yes and no. There are plenty of jobs for engineers and designers, and an increasing set of opportunities in sales as well. But not so many employment chances for everyone else.

On the other hand, local businesses stand to benefit directly from new tools and services that help them connect with new customers, and the overall more efficient use of shared resources (collaborative consumption) holds the promise of helping to reduce our collective carbon footprint as well. There is a palpable sense of hopefulness about the future that you can't help but pick up on when hanging around so many entrepreneurs, and we hope that some of that rubs off on you as you go through this book.