Disability Insurance pays a monthly benefit if someone gets disabled or sick and is unable to work . In Canada on average, 1 in 3 people will be disabled for 90 days or longer at least once in their working years. Disability benefits can be based on the salary you wish to maintain in event of a disability or on a loan payment that would be made for you like a mortgage. 

A significant difference between death and disability is that when someone dies, they stop producing bills. They no longer eat, require shelter and clothing etc but when someone becomes disabled, they require an ongoing income to survive.