it saw innovations such as trading companies, big businesses, contracts, bills of exchange, long-distance international trade, the first forms of partnership ("mufawada") such as limited partnerships ("mudaraba"), and the earliest forms of credit, debt, profit, loss, capital ("al-mal"), capital accumulation ("nama al-mal"), circulating capital, capital expenditure, revenue, cheques, promissory notes, trusts (see "waqf"), startup companies, savings accounts, transactional accounts, pawning, loaning, exchange rates, bankers, money changers, ledgers, deposits, assignments, the double-entry bookkeeping system, lawsuits, and agency institution.