A hashtag is a word or phrase preceded by the "#" symbol, used primarily on social media platforms to categorize content. By adding a hashtag to a post, users can make it easier for others to find related content. For example, using the hashtag #Travel allows people interested in travel to discover posts about trips, destinations, and travel tips. Hashtags originated on Twitter in 2007 and have since become a common feature across various platforms, including Instagram, Facebook, and TikTok. They help users engage with specific topics, join conversations, and increase the visibility of their posts to a broader audience.