Explanation:

He understood the importance of currency as a medium of commercial exchange and that is why he took keen interest to circulate gold and silver coins.The gold coin was introduced as Dinar. Tughlaq’s silver coin was named Adl. However, it was difficult to maintain the supply of gold and silver coins on a large scale.So,Tughlaq replaced those coins and started the circulation of copper and brass coins as the token currency which had the same value of gold or silver coins in 1330-32 CE.He was well aware that the state had to act as a responsible guarantor for the token money by ensuring high degree of security which will prevent others from making fake currencies.