An obligation is defined as a juridical necessity to give, to do or not to do. This means that non-compliance with an obligation can result in legal or juridical sanctions. The term "obligation" is derived from the Latin word "obligare," which means "to bind". It has been described as a legal relation between one person and another, where one is bound to fulfill a prestation which the other may demand. It is also seen as a juridical relation where a person (the creditor) can demand specific conduct from another person (the debtor), and can obtain satisfaction from the debtor's assets in case of breach.

Essential elements:

• An active subject, also called the obligee or creditor, who is the possessor of a right and in whose favor the obligation is constituted. This is the person who may demand the performance.
• A passive subject, also called the obligor or debtor, who is the person bound to perform the prestation. This is the one from whom performance can be demanded.
• The object or prestation, which is the subject matter of the obligation. This is the determinate conduct required of the debtor, which can be to give, to do, or not to do.
• The efficient cause, also known as the vinculum or juridical tie, which is the reason why the obligation exists. It is the legal tie that binds the parties.

Obligations can be classified in various ways based on the prestation or other factors. Based on the prestation, they can be:

• Real obligations: The obligation to give a specific thing.
• Personal obligations: The obligation to do or not to do.

Based on their demandability, obligations can be pure obligations (immediately demandable) or conditional obligations or those with a term (demandability depends on the happening of a future or uncertain event or the arrival of a certain period). Obligations can also be classified as divisible or indivisible, depending on whether the object or act is susceptible of partial performance.

Obligations arise from sources such as law, contracts, quasi-contracts, delicts (crimes), and quasi-delicts (torts).