universe's expansion

The universe is expanding like a balloon inflating; space itself is stretching, causing galaxies to move away from each other. This expansion started with the Big Bang around 13.8 billion years ago. Instead of galaxies traveling through space, space itself is growing, making distances between galaxies larger over time. This ongoing expansion is supported by observations, such as distant galaxies appearing to move away faster, indicating the universe is continually growing. The expansion affects everything on cosmic scales and helps scientists understand the universe's history and future evolution.