LinkedIn is a professional social media platform with over 65 million members from around the world. It focuses on professional networking and career development. The document provides tips on using LinkedIn for business purposes such as increasing visibility, connecting with potential clients and partners, tracking startups and competitors, and promoting your business as an industry expert through features like posting updates, answering questions, and participating in groups. Regular engagement includes creating a comprehensive profile, connecting with colleagues and contacts, and checking LinkedIn at least weekly to maintain your online presence.