Fixed loans are idea when interest rates are on the rise. With fixed rates whatever the interest rate is at the time you apply for your loan (note rate lock fee might apply), the interest rate is fixed for the term you choose. So say if you choose to have a 3 year fixed product at 7%, your interest rate will not either rise or fall for that whole 3 year period.
This is quite useful for clients that wish to have a set repayment for a certain period without any fluctuations. However, there is a downside to fixed rates. You are usually limited to extra repayments you are able to make on your home loan as well as if there is a fall in interest rates you have to remain on your fixed rate until the period ends. On the positive side, if interest rates rise you would be better off selecting a fixed mortgage product. Also you are able to have this product either for investment loans, owner occupied or land loans.