Welcome to the World With 2 Billion People Simulator, a free text-based simulation that explores what our planet might look like if its population were reduced to roughly 2 billion inhabitants, a level last seen around the early 1900s. Step into a world where cities are quieter, forests have reclaimed former suburbs, and the pace of life follows a different rhythm. This simulator brings to life the economic, environmental, cultural, and social shifts that such a dramatic change in population could bring, from the availability of resources and the state of global infrastructure to the evolution of technology, food systems, and everyday community life. Every corner of the globe is shaped by the question of how humanity adapts when so many people are no longer part of the picture, offering a thoughtful and immersive look at the relationship between people, nature, and the planet they share.