When the application context is ready to accept different levels of exactness in solutions and is supported by human perception quality, then the term ‘Approximate Computing’ tossed before one decade will become the first priority . Even though computer hardware and software are working to generate exact results, approximate results are preferred whenever an error is in predefined bound and adaptive. It will reduce power demand and critical path delay and improve other circuit metrics. When it comes to traditional arithmetic circuits, those generating correct results with limitations on performance are rapidly getting replaced by approximate arithmetic circuits which are the need of the hour, and so on about their design.