Multiple Internet-based companies are based in San Francisco.
Airbnb is an online marketplace and hospitality service , enabling people to lease or rent short-term lodging including vacation rentals , apartment rentals , homestays , hostel beds , or hotel rooms . Craigslist ( stylized as craigslist ) is an American classified advertisements website with sections devoted to jobs , housing , personals , for sale , items wanted , services , community , gigs , résumés , and discussion forums . Pinterest is a web and mobile application startup that operates a software system designed to discover information on the World Wide Web . Reddit ( stylized as reddit , [ ˈrɛdɪt ] ) is an American social news aggregation , web content rating , and discussion website . Salesforce.com ( styled in its logo as salesƒorce ; abbreviated usually as SF or SFDC ) is an American cloud computing company headquartered in San Francisco , California . San Francisco . San Francisco is also the headquarters of five major banking institutions and various other companies such as Levi Strauss & Co. , Gap Inc. , Salesforce.com , Dropbox , Reddit , Square , Inc. , Dolby , Airbnb , Weebly , Pacific Gas and Electric Company , Yelp , Pinterest , Twitter , Uber , Lyft , Mozilla , Wikimedia Foundation , Craigslist and Weather Underground . Twitter ( [ ˈtwɪtər ] ) is an online news and social networking service where users post and interact with messages , `` tweets '' , restricted to 140 characters . Weather Underground is a commercial weather service providing real-time weather information via the Internet . Weebly ( [ ` wibli ] ) is a web-hosting service featuring a drag-and-drop website builder .