Group 1

Pure Obligations: No conditions or terms are attached; demandable immediately.
Conditional Obligations: Depend on future, certain events or past events unknown to parties.
- Suspensive Obligation: Performance arises after condition is fulfilled.
- Resolutory Obligation: Obligation extinguished upon the happening of the condition.

Art. 1179: Obligations not dependent on future/unforeseen events are demandable at once.
Art. 1180: Debtor's obligation to pay when able is deemed as one with a period.
Art. 1181: Rights depend on fulfillment of the condition; no debt if the condition fails.
Art. 1182: Conditional obligations void when dependent solely on debtor's will.
Art. 1183: Impossible conditions or those against public policy lead to void obligations.
Art. 1184/1185: Time conditions extinguish obligations on expiration if unmet; negative stipulations make obligations effective upon non-occurrence.
Art. 1186: If obligor prevents fulfillment, the condition is considered fulfilled retroactively (Art. 1187).

Art. 1188: Creditors can take measures to protect their rights before fulfillment; demand varies based on condition type.
Art. 1190: Upon conditions being fulfilled with obligations to give, mutual restitution applies.
Art. 1191: If one party breaches a reciprocal obligation, the other can demand compliance or rescission.
Art. 1192: In mixed breaches, liability is tempered or may result in extinguishment without clear fault.

Art. 1193: Obligations with a fixed period are only demandable at that time; resolves if conditional.
Art. 1196: If no period is stated but implied, courts can establish it; generally benefits both parties.
Art. 1198: Debtor loses the right of period under certain conditions like insolvency or non-fulfillment of promises.

Alternative Obligations (Art. 1199): Multiple prestations, performance of one suffices; the right to choose generally lies with the debtor unless specified otherwise.
Facultative Obligations (Art. 1206): Only one prestation due, but debtor may substitute; loss of principal extinguishes obligation, while loss of substitute doesn't make debtor liable until substitution occurs.