SAN FRANCISCO — Your holiday shopping list probably includes gadgets, games and gizmos that illustrate how technology is changing the way we work, play and communicate. So why not throw in a few books about the people and services causing the delight and disruption? Here are a few suggestions:

"The Twitter Book" ($19.99) by Tim O'Reilly and Sarah Milstein ($19.99); "Twitter Tips, Tricks and Tweets" ($19.99) by Paul McFedries and Pete Cashmore; "Twitter Wit" ($12.99) edited by Nick Douglas.

Twitter isn't quite as powerful as Google, but can be an interesting and fun communications tool. It's even better if you learn how to make the most of it.

Both "The Twitter Book" and "Twitter Tips, Tricks and Tweets" make sense of the Twitterverse's lingo and etiquette, and they point out other twitterific services and applications.

"Twitter Wit" is a whimsical collection of the best tweets so far, pithy posts that say a lot in 140 characters or less. Even if they don't inspire you, tweets like these might make you smile (or grimace): "A hangover is the wrath of grapes" and "The baggage carousel sounds a lot more fun than it actually is."

"Behind The Cloud" ($27.95) by Marc Benioff and Carlye Adler.

Contrary to popular perception, Salesforce.com founder Marc Benioff didn't invent "cloud computing" — a catchall for software programs that are made available over Internet connections instead of being installed on individual computers. But there's no question about this showman's role as the chief evangelist for the idea, which generates more than $1 billion in annual revenue at Salesforce.com. Few believed Benioff could pull it off when he started Salesforce.com a decade ago. Find out why people listen to him now.

"Smasher" ($14.95) by Keith Raffel.

This novel is a thriller with a Silicon Valley twist. The bad guys are a ruthless high-tech CEO (obviously based on Oracle's Larry Ellison with a touch of Apple's Steve Jobs) and a back-stabbing physicist whose conniving landed him a Nobel Prize. The hero is Ian Michaels, who spends most of the novel trying to preserve his startup's independence, restore his great aunt's legacy and find out who tried to kill his wife, a prosecutor.

It helps that the author knows about intrigue, having once held top-secret clearance to keep an eye on the CIA for a Senate committee. He also knows his way around Silicon Valley: He ran a smaller rival to Salesforce.com before selling it six years ago for at least $56 million.