The emergence of many non-linear loads causes severe disturbances in the present power system. It affects the power quality thereby decreasing the overall efficiency. The important issue among the power quality is harmonics that becomes the major concern in the power system network. This survey mainly discusses the causes and effects of harmonics in the electrical network. It also discusses the various detection techniques that detects and analyzes the presence of harmonics in the system. In addition to this, this survey also discusses the new technique called PAN TOMPKINS algorithm to detect the harmonics with the communication protocol as cloud computing.