They don't, at least not literally. Unlike air conditioning, ceiling fans do not directly affect air temperature. However, this does not mean that the ceiling fan does not effectively dissipate heat.
Two purposes listed in the question (I) :
Regardless of the room temperature, moving air from the ceiling fan will help you feel cool. This is very similar to what happens outside of summer - it can be 80-90 degrees, and if there is a breeze, it will be very pleasant.
2. The circulation from the ceiling fan can spread cold air from lower areas (and air conditioners) into the center of the room.
Type IIA. How does the ceiling fan help heat in winter?
It's very similar to their help in circular cooling. During the winter, hot air rises to the ceiling, and most of the heat is wasted. It can save a lot of heat by running the ceiling fan in winter, pushing the warm wind from the ceiling and eliminating the cold spots.
The ceiling fan has two purposes.
1. Provide a breeze to create "wind chill factor" 2. Make air circulate throughout the room or area.