The Big Bang Theory is the leading explanation for the origin and evolution of the universe. It posits that around 13.8 billion years ago, the universe began as an infinitely small, hot, and dense point, known as a singularity. It then rapidly expanded in a process called cosmic inflation, cooling down and forming matter, stars, galaxies, and eventually the large-scale structures we observe today. The theory is supported by key observations, such as the cosmic microwave background radiation and the redshift of distant galaxies, which suggest that the universe is still expanding.
