1. Authentic is an adjective that describes the authenticity and credibility of something. It conveys the idea that an object or person is real and unaltered, possessing genuineness and reliability. For instance, when we describe a painting as an authentic masterpiece, it means that the painting is a true work of art, not a forgery or modified.2. Era, on the other hand, is a noun that represents a specific historical period or epoch. It encompasses the distinct characteristics and significant events of that time. For example, the Industrial Revolution marked the beginning of a new era, which is not just a timestamp but also a symbol of the important changes and progress that occurred during that period.In summary, the difference between authentic and era lies in their roles and the aspects of things they describe. Authentic emphasizes the authenticity and reliability, while era focuses on the characteristics and significant events of a specific historical era. Both serve different purposes in linguistic expression.