No, black salt and sendha namak are not the same. Black salt is a type of mineral-rich volcanic rock salt that is dark in color due to its high iron content.  It has a slightly sulfurous smell and a pungent flavor, making it popular in Indian cuisine.  Sendha namak, on the other hand, is an unrefined sea or rock salt harvested from natural sources such as shallow ocean beds or mountainside mines.  Unlike black salt, it contains no added minerals or sulfur compounds, resulting in a purer taste and lighter color.  Each type of salt offers its own unique flavor profile, which can be used to enhance different dishes.  Black salt is often used to add a savory, smoky flavor to Indian curries and chaats, while sendha namak can be used as a substitute for table salt in recipes or added to yogurt-based dishes.