Representative funds are promised by the government or the bank to exchange a certain amount of silver or gold. For example, the old pound bill or pound has been guaranteed to be converted into a pound of sterling silver. For most of the nineteenth and twentieth centuries, most currencies represented the currency by using the gold standard. Representative funds have now been replaced by a fixed currency. Fiat is “let it complete” in Latin. Money is now valued through government decrees or decrees. In other words, an enforceable legal currency law has been enacted. According to the law, it is illegal to refuse “legal currency” funds to support some other form of payment. The source of the “$” currency symbol is uncertain. Many historians trace the “$” money mark back to Mexican or Spanish “P” for pesos, piastres or eight pieces. Research on old manuscripts shows that “S” is gradually written on “P” and looks very much like the “$” mark.