Leave-in conditioner is a type of hair product that is designed to be left in the hair after washing or conditioning. Unlike rinse-out conditioners that are washed out after a few minutes, leave-in conditioners are designed to be applied to the hair and left in without rinsing. Leave-in conditioners are usually formulated with moisturizing ingredients such as oils, humectants, and proteins. These ingredients help to hydrate the hair, protect it from environmental damage, and reduce frizz and breakage. Leave-in conditioners can also help to detangle the hair and make it more manageable.