In this dissertation a short summary is given on the main lower order aberrations (myopia, hyperopia, presbyopia and astigmatism), and then Higher Order Aberrations(HOA) are described in a bigger extent. Concerning HOA, the Zernike polynomials are described as the main tool for understanding and categorizing them. The importance of the Zernike polynomials in the clinical practice is also mentioned as well as the RMS (root mean square) which enables the ophthalmologist understand and therefore better manage the HOA. Further on, a big part of the dissertation is devoted on the examination of the HOA. The examinations include the Shack Hartmann technique which is extensively explained, the examination of the chromatic aberrations, and in less extend the SRR (spatially resolved refractometer) which is a method using an alternative approach. The symptoms of the HOA are then mentioned and the possible treatment options, namely the eyeglasses the contact lenses and the custom LASIK, are emphasized. Finally, some thoughts about the future are shared and ways by which the technology can be improved to match the expectations of the ophthalmologists and patients alike.