The contract of suretyship or guaranty is one whereby a person obligates himself to pay the debt of another in consideration of a benefit flowing to the surety or in consideration of credit or indulgence or other benefit given to his principal, the principal in either instance remaining bound therefor. Sureties, including those formerly called guarantors, are jointly and severally liable with their principal unless the contract provides otherwise. There shall be no distinction between contracts of suretyship and guaranty.