Periodic money payments payable by a non-custodial parent, to the custodial parent, for the care of his or her minor child.
When two parents separate, it is often determined that a child will primarily reside with one of the separated parents, the other exercising access or visitation rights from time to time. In those situations, the parent with the primary residence responsibilities will incur most of the child-related expenses: food, accommodation, clothing, groceries, utilities, transportation, school, lessons etc.
To reflect that inequity, the common law, and then by statute, has established that each parent has a legal obligation to support their child.
For the parent who does not have the child living with her/him, this means equally or fairly contribute to their child's expenses and needs.
This is done by requiring that parent to make monthly or other periodic (rarely a lump sum or annual payment) to the other parent as a contribution towards the expenses of raising a child.
Some jurisdictions prefer the term child or family maintenance but the latter term has the disadvantage of referring, too, to spousal support.
Further, many jurisdictions have established guidelines based on the actuarial analysis of the cost of raising a child or children. In those cases, the person paying child support (sometimes called the payor) declares his annual income and the amount to pay is based on the actuarial tables or "child support guidelines". The money is paid directly to the parent who sustains the child’s primary residence (sometimes a child support recipient) or through a government child support collection agency, which acts as an intermediary between the payor and the recipient.
There are unique rules to deal with child who are no longer minors, who have special or extraordinary needs or expenses, and when a child or the children spend close to equal time with, and maintain residence in the homes of, both parents.
References or further reseach:
► Child Support Agency of Great Britain
► USA Administration for Children and Families
► The federal (Canada) Child Support Guidelines
► Child Support Law in Canada
► Child Support Agency of Australia
► UIFSA (interstate enforcement - USA)