Some stuffs to note:
Sharia prohibits the payment or acceptance of interest fees for the lending and accepting of money respectively, (Riba, usury) for specific terms, as well as investing in businesses that provide goods or services considered contrary to its principles (Haraam, forbidden).
The basic principle of Islamic banking follows the laws of Sharia, known as Fiqh al-Muamalat (Islamic rules on transaction). The term "Islamic banking" is synonymous with "full-reserve banking" and "Sharia-compliant banking" The most prominent feature of these laws is usury – the prohibition of paying or collecting interest on funds. The Islamic terminology for this is riba or ribaa. The Sharia also forbids engagement in investments that include financial unknowns such as buying and selling futures, as well as businesses that are haraam – dealing in products that are contrary to Islamic law and values such as alcohol, pork, gossip or pornography. These principles apply to all individuals, companies and governments.
Banks that comply with Islamic law are forbidden to charge interest or late payment fees, which is also considered a type of riba. To minimize risk, banks will often require a large down payment on goods and property, or insist upon large collateral. It is lawful for the Bank to charge a higher price for a good if payments are deferred or collected at a later date since it is considered a trade for goods rather than collecting interest.
Islamic Banking is growing at a rate of 10-15% per year and with signs of consistent future growth
According to (CIMB) Group Holdings, Islamic finance is the fastest-growing segment of the global financial system and sales of Islamic bonds may rise by 24 percent to $25 billion in 2010.
In an Islamic mortgage transaction, instead of loaning the buyer money to purchase the item, a bank might buy the item itself from the seller, and re-sell it to the buyer at a profit, while allowing the buyer to pay the bank in installments. However, the bank's profit cannot be made explicit and therefore there are no additional penalties for late payment. In order to protect itself against default, the bank asks for strict collateral. The goods or land is registered to the name of the buyer from the start of the transaction. This arrangement is called Murabaha. Another approach is EIjara wa EIqtina, which is similar to real estate leasing. Islamic banks handle loans for vehicles in a similar way (selling the vehicle at a higher-than-market price to the debtor and then retaining ownership of the vehicle until the loan is paid).
Some Islamic banks charge for the time value of money, the common economic definition of Interest (Riba). These institutions are criticized in some quarters of the Muslim community for their lack of strict adherence to Sharia.