Heating and cooling loads can be divided into two main categories: sensible and latent. Sensible loads refer to the energy required to raise or lower the temperature of the air, while latent loads refer to the energy required to add or remove moisture from the air.

Within the sensible load category, there are two types of loads: sensible heat gain and sensible heat loss. Sensible heat gain is the energy required to raise the temperature of the air, while sensible heat loss is the energy required to lower the temperature of the air. Within the latent load category, there are two types of loads: latent heat gain and latent heat loss. Latent heat gain is the energy required to add moisture to the air, while latent heat loss is the energy required to remove moisture from the air.