This section is from the book "The Law Of Contracts", by William Herbert Page. Also available from Amazon: Commercial Contracts: A Practical Guide to Deals, Contracts, Agreements and Promises.
If two or more persons constitute one party to a contract, the question as to the nature of their rights and liabilities presents itself. If two or more persons are promisors in a contract, their liability may be joint, or several, or joint and several. If their liability is joint, each of the promisors is liable, and may be held for the entire liability arising under the contract.1 A several contract is one in which each of the promisors undertakes only a limited amount of the entire liability,2 or which in each severally undertakes the entire liability.3 A joint and several contract is one which at the election of the promisee he may treat either as a joint contract or as a several contract. In Louisiana, by statute, different terms are employed. "A joint obligation" is used to express substantially the idea which at Common Law is expressed by "several contract," while the term "solidary obligation" is used to express the idea which the Common Law expresses by "joint contract." "A joint obligation under the laws of Louisiana binds the parties thereto only for their proportion of the debt, whilst a solidary obligation, on the contrary, binds each of the obligors for the whole debt."4