I am a big fan of taking public transit whenever I can. It's more efficient, better for the environment, and reduces stress when commuting (compared to driving alone). There are so many ways to get around the Bay Area using public transit.
For travellers new to San Fran, BART San Francisco (which stands for Bay Area Rapid Transit) is a public subway system for the Bay Area of San Francisco. BART, despite conjuring up images of the troublemaking Simpsons character, is an enjoyable way to travel, unlike most crowded and cramped subway systems. - Epictourist