Both FUE (Follicular Unit Extraction) and DHI (Direct Hair Implantation) are hair transplantation techniques that involve extracting hair follicles from the donor area and implanting them into the recipient area. The main difference between the two methods is the way hair follicles are implanted. In FUE, hair follicles are transplanted using a medical punch, while in DHI, they are implanted using a specialized tool called a Choi pen.