An ionizer is a device that uses electrical charges to produce ions, which are atoms or molecules that have gained or lost electrons. These ions can help purify the air by attaching to airborne particles, such as dust, pollen, and smoke, causing them to clump together and fall to the ground or be trapped in filters. Ionizers are often used in homes and offices to improve indoor air quality. They can be found in various forms, including air purifiers and water ionizers, which are designed to enhance the cleanliness of air and water, respectively.