(What is the difference between humid, wet, and moist?) I would say that wet is best used when describing water on a surface. "The sidewalk was very wet after the heavy rain." "Why are you so wet? Because I just got out of the pool." "The floor can be slippery when wet." Moist is kind of like wet, but there will be less liquid involved. A towel that is not quite dry is moist, but like panther said a cake can also be moist. You should not describe a cake as being wet, unless it has just been dumped in water! Spongy things are often the most likely to be described as moist. Like cake, wet grass, or sponges them selves often are moist. "The ground is still a little moist after the morning's dew." "Eww, gross, this sponge is still moist." "This cake is much more moist than your last one." Humid describes the amount of moisture in the air. Often hot days are very humid as well. "I think the humidity is suppose to go up again today. Well thank goodness we have an air conditioner then!" "This low humidity is making my skin crack." "Uh, the air is so humid it is making my hair into a puff ball!" You know it's very humid when the air feels sticky. The jungle is very humid while the desert is not humid at all.