Tcredits are a Tcurrency. Just like Naira is the official currency of Nigeria, Dollars is the USA's, Euro is Europe's etc. However, Tcurrency isn't Tcredit. Tcurrencies are any acceptable exchange option. This of cos means whatever is acceptable generally as payment for purchases made can be defined as Tcurrency. For instance, on Tripleclicks, Tcredits are Tcurrency. So is MRP's cos we can purchase stuff using our MRP's.