The Photovoltaic (PV) systems and the semiconductor PV technologies are heavily impacted by shading conditions; total or partial. Nearby residential buildings, commercial buildings, objects, etc. are likely to cause shade on the PV installations.  This study focuses on the evaluation of the effect of shading on thin-film PV modules, which were analyzed under two categories: single thin-film module and a string of modules installed at the University of Gävle, Sweden. The measurement was made by using METREL MI 3109 Euro test instrument. The study intends to help researchers to analyze the variation in the output performance parameters and behavior considering different types of shading on the thin-film modules. Experiments have been performed by creating full and partial shading (uniform and nonuniform) by using plastic foil, opaque board, wooden pole, and tape to emulate different types of natural shading conditions.  The findings show a loss in power due to shading. In the single thin-film modules, which do not have any diode between the cells; reverse breakdown, power dissipation and generation of hot spots are caused by the cells which are partially shaded.  In the string of modules installed at the University of Gävle, Sweden; under partial shading conditions the diodes are activated below certain voltage when current is high, leading to current bypass and therefore prevents the module from the damage caused by high heat generation. Under the condition of extremely low shading by a wooden pole, the diodes were not activated; however reverse breakdown was observed similar to the case of partial shading in single thin-film modules.