Here is what, what you want to know about interest. Interest is the money paid at regular intervals (daily, weekly, monthly or quarterly, half-yearly or yearly) at a particular rate as rent for the money lent. It is the cost of using somebody elses money. When you borrow money, you pay interest. When you lend money, you earn interest. Interest is calculated as a percentage of a loan (or deposit) balance, yet to be repayed. The page is dedicatedly designed with providing you the knowledge on different types of interest and its utilities.
The interval of interest payment can be decided upon agreement between the lender and borrower. The amount of interest paid depends on the interest rate, which is usually quoted as a percentage rate per year. Interest is classified as "Simple Interest" (interest for balance of original principal) and "Compound Interest" (interest for balance of original principal plus unpaid interest).