Child support is a way for a noncustodial parent to help pay for the expenses of the children because it isn't right for one parent to shoulder the entire financial burden of the kids. For the most part, the child support is ordered by the court, which means that the paying parent must cover at least that amount. It doesn't mean that it is the maximum that the parent can spend on their children.
One thing that is confusing about child support for some people is what it is supposed to cover. In a nutshell, these payments are meant to help with the costs of the child's basic needs. Once those are paid, the support payments can be used for anything else related to the child. Because housing, food and utilities are basic needs, the child support payments might be used to pay for those even though others in the home also enjoy the benefits of them.
How these support payments are made might confuse some people. For the most part, basic child support is done through paycheck withholding now. The recipient parent receives a direct deposit with the funds. There might be other payments that have to be made. These are usually for things like shares of out-of-pocket medical expenses, child care or school expenses. It is a good idea to have these handled through a trackable method, such as check or money order. No matter how it is paid, always get a receipt.
Be sure that you review the child support order, so you know what it entails. Not understanding it isn't a valid reason to not comply. You can face penalties if you don't pay as ordered, so do what's best for your kids and make the payments as stipulated in the court documentation.