The Casimir Effect is a physical phenomenon that occurs when two uncharged, parallel plates are placed very close together in a vacuum. Due to quantum fluctuations, virtual particles pop in and out of existence between the plates, creating a pressure that pushes them together. This effect is a direct consequence of the principles of quantum mechanics. This phenomenon was first predicted by physicist Hendrik Casimir in 1948. The Casimir Effect has implications in various fields, including quantum field theory and nanotechnology, as it demonstrates the influence of quantum forces in seemingly empty space.