A more thorough explanation:

Civil marriage is a legal union between two people as husband and wife. It requires parties who are legally capable of contracting to marry, mutual consent or agreement, and an actual contracting in the form prescribed by law. Marriage has important consequences in many areas of the law, such as torts, criminal law, evidence, debtor-creditor relations, property, and contracts.

For example, if John and Jane want to get married, they must meet the legal requirements and obtain a marriage license. They must also have mutual consent to marry and exchange vows in a ceremony that follows the legal requirements. Once they are married, they have legal rights and responsibilities towards each other, such as the right to inherit from each other and the responsibility to support each other.