The document summarizes various social media case studies of different brands' usage of platforms including Facebook, LinkedIn, Google+, Twitter, Snapchat, YouTube, and Pinterest. It explores how FitBit, Philips Healthcare, H&M, Taco Bell, Sour Patch Kids, Dollar Shave Club, and Wayfair have effectively utilized features and engaged audiences on these respective platforms. Key reasons for success included knowing the target audience and choosing the appropriate platform, using platform features to engage and inspire, and producing creative and entertaining content.