Green screen technology originated from early filmmaking techniques in the late 19th and early 20th centuries where visual effects were created by painting glass and placing it between objects and the camera. These early techniques were time-consuming and limited, so green screen technology was developed, which uses a green or blue background that can be digitally replaced during post-production, allowing filmmakers to shoot actors against a blank backdrop and place them in virtual sets. Green screen has now become a standard technique used in many major films and TV shows to create complex visual effects and environments that were previously impossible.