What is Unemployment Insurance?

Legal Definition
Unemployment insurance (雇用保険 koyou hoken), also known as 失業保険 (shitsugyou hoken) is the "user pays" system of unemployment benefits that operate in Japan. It is paired with Workers' Accident Compensation Insurance (労働者災害補償保険 rousai hoken) and referred to collectively as Labor insurance (労働保険 roudou hoken). It is managed by Hello Work.
-- Wikipedia
Legal Definition
Government welfare scheme where money is given to those unemployed through no fault of their own making.