A more thorough explanation:

A child born to parents who are not married to each other is called a child out of wedlock. This term is also known as an illegitimate child. In the past, illegitimate children had fewer legal rights than children born to married parents. However, today, most countries have laws that protect the rights of all children, regardless of their parents' marital status.

For example, in the United States, an illegitimate child has the right to inherit from their mother, and in some cases, from their father as well. They also have the right to financial support from both parents, just like any other child.

Other terms related to children include:

• Biological child: A child who is related to their parents by blood.
• Adopted child: A child who is legally made a part of a family through adoption.
• Stepchild: A child who is the child of one's spouse from a previous marriage.
• Dependent child: A child who is in need of support and care because of the death, absence, or incapacity of their parent or legal guardian.
• Special-needs child: A child who has medical problems or a physical or emotional handicap that requires special care.