There are several types of windows commonly used in buildings, each serving different purposes. Casement windows open outward with hinges on one side, allowing for maximum ventilation. Double-hung windows have two sashes that slide up and down, making them easy to clean and versatile for airflow. Another popular type is the sliding window, which moves horizontally and is ideal for spaces where a swinging window may not fit. Bay windows extend outward from the main walls, creating a nook and enhancing natural light. Each type offers unique benefits depending on design and functionality needs.