It's a sad statement on our modern world when you can say "pedo sites" and everyone instantly gets it: "Oh of course, he's talking about sites where pedophiles go to get together and talk about pedophile stuff, share pictures, that kind of thing. Sure, pedo sites -- it would be surprising if they didn't exist."

Sensitive as ever to its portrayal by media, dating app Tinder has moved on from unflattering magazine articles to out of home advertising. This time Tinder is taking issue with a billboard paid for by the AIDS Healthcare Foundation in Los Angeles, claiming there is a link between Tinder and Grindr, its gay predecessor, and various genital unpleasantries.

Narendra Modi, India's charismatic Prime Minister, praised social media for enabling ordinary citizens to express political opinions and influence their governments during a visit to Facebook over the weekend. The visit was part of a tour of Silicon Valley before Modi headed to New York City for the United Nations summit scheduled for this week.

This week brings even more evidence that social media usage is correlated with sleep loss and related negative outcomes in teenagers. The latest study comes from the University of Cardiff in Wales, where researchers investigated teen social media habits and found that over a third of teens wake up in the middle of the night to check social media every week.

While LinkedIn has more or less cornered the professional social networking market, new entrants are targeting niche sectors of the business world. One Boston-based startup, Alignable, launched a social network in January 2014 to connect small businesses that can cooperate with each other due to physical proximity.

Are you more a "color" commentator or a play-by-play person? Do you find yourself surfacing random pieces of trivia about the athletes you're looking at or do you tend to describe what's going on on the field in minute detail, as if out of some need to constantly affirm reality?

The salad days of social commerce have come and gone, judging by the woes of group buying and daily deals sites. In the latest fillip of bad news, Groupon has revealed that it will lay off around 1,100 employees over the next few months, most in overseas divisions. That's about 10% of the company's total workforce.

With their insatiable appetite for constant updates and tiny attention spans, journalists naturally gravitated to Twitter when it launched and have been some of its most dedicated users ever since. But now the microblogging site is facing new competition from Facebook, which hopes to pry journalists away from Twitter with Signal, a new feature that provides a real time view of what's happening the Facebook universe, including Instagram.

The world's largest social network is barreling into e-commerce through an expanded relationship with e-commerce platform Shopify. It will allow Facebook users to buy products directly from Shopify merchants on their Facebook pages.

The worlds of business information and social media are fast converging, judging by a flurry of new deals between social networks and publishers of financial data. In the latest such tie-up, Bloomberg has signed a long-term agreement with Twitter, giving the financial information distributor access to real-time information from the microblogging platform on behalf of subscribers to the Bloomberg Professional service.