The document discusses the expansion of influencer marketing on social media. It defines influencer marketing as collaborations between companies and popular social media users to promote products or services. As social media platforms grew, more influencers emerged with dedicated followings, leading companies to work with influencers. The types of influencers are described based on number of followers. Current and future trends of influencer marketing expanding on platforms like TikTok and through smaller influencers are also outlined.