All the refrigerator and freezer need to frost.
Some can defrost automatically, the others need to defrost manually.
Normally, the fridge compartment can defrost automatically.
A. These products can defrost automatically
B. These need defrost manually
Precautions useful to prevent or mitigate the frost:
•Make sure that high humidity products are stored properly, and cool food to ambient temperature before storing.
The food should be covered or packaged, etc.
How to defrost , please see the FAQ <How to clean our refrigerator> OR < How to defrost the chest freezer >