Photonic crystal devices are periodic structures of alternating layers of materials with different refractive indices. Waveguides that are confined inside of a photonic crystal can have very sharp low-loss bends, which may enable an increase in integration density of several orders of magnitude. This is a study of a photonic crystal waveguide. The crystal features a grid of GaAs pillars. Depending on the distance between the pillars, waves within a certain frequency range will be reflected instead of propagating through the crystal. This frequency range is called the photonic band gap. When some of the GaAs pillars in the crystal structure are removed, a guide for the frequencies within the band gap is created. Light can then propagate along the outlined guide geometry.