What is vested bonus how it is different to cash bonus

Vested means that what ever the award or item is is now really entirely the one it was awarded to. Most commonly in something like a 401K plan, if the company provides a matching contribution, or awards stock bonus, the amount of either may not be allowed to be taken or withdrawn, or really becomes fully owned, by the employee for some time....frequnetly 25% of it each year is ... for 4 years....at which point 100% of it is vested to the employee.