There are two types of loading:
Front Loading: It allows you to add the laundry by opening the door which requires slightly more space than the top loading machines. If your laundry room is small in space, this washer can be stacked.The space required to open the door may vary with the door opening angle which is normally 90 to 180 degree.
Top Loading: In this type of loading you have to add your laundry from the top. Some top-loading machines still provide you the freedom of adding laundry even after the cycle has started.The door can be detachable or fixed in this type of loading unlike front loading washing machines.