Hair weaving is a type of hair extension service that involves attaching hair extensions to a person's natural hair by weaving them in. This technique is commonly used to add length, volume, and thickness to hair. Hair weaving can be done using a variety of materials, including human hair, synthetic hair, and animal hair. The process of hair weaving involves braiding the natural hair into a series of cornrows, and then sewing the hair extensions onto the braids. The extensions are typically sewn in using a needle and thread, and can be attached in a variety of patterns to create different styles.