Columbia is the name of the personification of America. That means she's like a pretend lady who represents the whole country, kind of like how Santa Claus represents Christmas. She's named after the explorer Christopher Columbus, who many people think discovered America. People started using Columbia as a nickname for America because it sounds similar to Columbus. You might hear people use the name Columbia when they talk about things like the capital city (Washington, D.C.) or famous landmarks, like the Columbia River or Columbia University. Even though Columbia isn't a real person, lots of people like using her name as a way to show their pride and love for America.