"Hair porosity determines your hair’s ability to absorb and retain moisture, as well as how oils pass in and

out of the hair's cuticle," explains hairstylist and color expert, Sharon Spellman. "Essentially, the higher the porosity is, the more exposed your hair becomes." Celebrity hairstylist Christin Brown agrees, adding that porosity also has a lot to do with how well moisture is able to enter and remain inside the hair shaft. As for the levels of hair porosity, there are three that are widely acknowledged: low, normal, and high porosity. "In a nutshell, hair porosity is the hair's ability to retain and accept moisture. Most folks in the natural hair community find this information useful when it comes to selecting the right products to help with benefits toward the hair's state," she says. Though talk of hair porosity is most common in the naturally curly and coily hair communities, Spellman says that everyone's hair, independent of hair type or curl pattern, can fall anywhere on the hair porosity spectrum.