The High Impedance Surface, abbreviated popularly as HIS, was first introduced to the microwave community by Daniel F. Sievenpiper in 1999. It possesses unique properties by virtue of its geometry and periodicity which makes it very useful in many different radio frequency (RF) and microwave applications. Ever since its inception, the HIS has continued to grow in popularity and usefulness throughout the years. In this paper, we look at the unique properties of the HIS and discuss how they originate. Moreover, we also discuss the different applications of the HIS which make it significant even after almost 25 years since it was first introduced.