Family Income Benefit works in a very similar way to Life Insurance.
You take out cover for an agreed sum and pay the premiums. If you pass away during the term of the policy, your family receives a payout from the insurer.
The major difference between Life Insurance and Family Income Benefit is how you receive the payout. Whereas with Life Insurance your beneficiaries get the payout as a single lump sum, with Family Income Benefit the payout is split into a more manageable income for the remainder of the policy term.
So if you passed away in year 10 of a 20 year policy, your loved ones would receive the agreed benefit on a regular basis for the next 10 years, allowing them to keep up with their outgoings and not have to worry about what to do with one large Life Insurance lump sum.