The 'S' of LASIK stands for 'surgical, ' which is the type of procedure used in LASIK eye surgery. LASIK, or Laser-Assisted In Situ Keratomileusis, is a type of refractive eye surgery that is used to correct vision problems such as nearsightedness, farsightedness, and astigmatism. During the procedure, a laser is used to reshape the cornea, which is the clear outer layer of the eye. This helps to improve the patient's vision by allowing light to be focused more accurately on the retina.