Jack Dorsey

Square makes it much easier for even the smallest retailers to accept credit cards: The mobile payment firm offers easy to use hardware that plugs right into iPhones or Android devices. But at least part of its new high price tag probably derives from the fact that its founder, Jack Dorsey, also co-founded Twitter.

The smartphone revolution is about to upend another business: credit card processing. With Google's new Android pay-by-phone app and Square's new transaction hardware for iPhones, your plastic could become obsolete.

In a move that has to make Google somewhat nervous, Twitter has redesigned its homepage so that non-Twitter members can search topics from Twitter.com, just as they can at Google.com, Yahoo.com or Microsoft's Bing.com. "We're eager to see if encouraging a sense of wonder and discovery leads to a...

I ran into Twitter co-founder Biz Stone at the Fortune Brainstorm Tech conference last week in Pasadena, California. After talking at length about why Twitter matters and how it'll succeed, I came away with this: It's probably too late for a tech giant to buy Twitter. "The truth is, we're not even...

Twitter suffered a security breach last week as an unemployed security hacker who lives in Europe broke into Twitter's online documents. The incident underlined the risk for people and companies who keep vital information on the Web. Yesterday, a detailed story on how the hacker was able to break...

Think of Twitter as another in-box. By following someone on Twitter, you are electing to receive mini Twitter e-mails, known as Tweets, from those new pals. But there is a growing problem: Those new pals may not be who they say they are. Fake users are not a big problem for Twitter - they help...

MySpace founders have been pushed aside and there is speculation layoffs are coming. As Facebook and Twitter watch what's happening at MySpace, they should be worried and heed the warning of potential problems to come. Social-networking sites grow like weeds and, well, die like weeds...

Twitter would have to consider selling itself, if it is best for the company, co-founder and Chairman Jack Dorsey told DailyFinance. "We have to put the product and the service that we're building first," Dorsey said in an exclusive interview with DailyFinance today after he spoke at New York...

With all the gloom in the global economy, I got to wondering whether there is anything else going on in the world of business. I'm looking for growth because I think that's what will ultimately bring the economy out of the doldrums. Not surprisingly, that growth is coming from technology companies....