If central air conditioning is not available in your workplace, school or home, a portable air conditioner is a great solution. Many models have swivel casters that make it easy to move from room to room; easy to adjust temperature controls and automatic timers that can be set to turn on and off as needed. Portable air conditioners have different BTUs, voltage and watts – be sure to choose the one that works best in your environment. In addition to cooling, these AC units also help control humidity and overall airflow. Other types of air conditioners include window and wall AC units and enclosure air conditioners, designed to maintain a specific temperature inside the enclosure.