As more and more sensitive information gets shared online, the need for cyber-security becomes stronger—especially on social networks, where we share megabytes’ worth of personal and professional data daily. In this week’s episode of Social Update, Sunny Lenarduzzi explains Facebook’s latest security initiative, ThreatExchange, which allows researchers to keep tabs on security threats and quickly exchange information in order to keep everyone’s accounts safe.

Another Facebook initiative launching shortly will allow users to buy and sell products in “For Sale” groups. Find out more about how to write up a Facebook listing, and when to expect this feature to appear on your network.

Expanding into different fields has its advantages, but there is also merit in being the best network for a very specific audience. Take LinkedIn, for example—the network’s reported earnings had a 45% year-over-year increase from 2013 numbers. Sunny will explain how LinkedIn has been winning in the professional network space over the past months.

And speaking of wins, you simply must learn about Footlocker’s latest Instagram campaign—it’s a fine lesson in innovative approaches to follower engagement on the photo network.

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