Paid to people who are responsible for a child up to the age of 16 (or 19 if still in full time non advanced education no higher than A level).
The benefit is not means tested but can affect the amount of other means tested benefits that you get, apart from tax credits where it is not counted as income.
It can also be necessary to be claiming this benefit if you wish to claim other means tested benefits for a child you have become responsible for (for example a grandchild or nephew).