Registered Retirement Income Funds are much similar to Registered Retirement Savings Plans with a little difference that in RRSP you contribute money as savings for your retirement whereas in RRIF you make regular withdrawals of income from the account after retirement. All the fund held under the RRSP account have to transferred to RRIF starting age 71 of the contributor and is subject to minimum withdrawal regulation. You are completely free to keep your investments in different vehicles like mutual funds, deposit certificates, bonds, shares, etc. You also have the option of naming your wife as nominee who will act as beneficiary in case of your death and all the RRIF amount will be rolled over tax free.
Minimum withdrawals are specified which must be made at regular intervals of time (specified by you and it can be monthly, quarterly, semi-annually or yearly) and you are given the option to choose from investments which must be sold to provide for inflow of cash.