Window installation is the process of fitting new windows into a building or replacing old ones. This involves measuring the window openings, selecting the right type of windows, and ensuring they are properly sealed to prevent air and water leaks. The installation typically requires tools like a level, caulk, and screws. Professionals or skilled DIYers can perform the task, but it's important to follow safety guidelines and manufacturer instructions for the best results. Proper installation enhances energy efficiency and improves the overall appearance of a home.