kinds of period
the obligation only begins only from a day certain upon arrival of the period
suspensive period (ex die)
the obligation is valid up to a day certain and terminates upon arrival of the period
resolutory period (in diem)
period when it is provided by laws
legal period
period when it is agreed to by the parties
conventional or voluntary period
period when it is fixed by the court
judicial period
period when it is fixed or known when it will come
definite period
period when it is not fixed or it is not known when it will come
indefinite period