The Credencial del Peregrino, the pilgrim's creditial, is needed to stay in albergues along the way. At each place we stop along the camino, we will get a stamp to show what we have walked. Stamps can be gotten at Hostels, Hostals, Hotels, Pensions, Cafes, etc.
If we fill up our Credencial we will purchase another along the way.
The pilgrims passport is our record of the places we have passed and will be stamped by the hospitalero in the albergues we stay, every bar, hostel along the camino. It is necessary to get at least one stamp per day. Proof that we have not cheated and gone by car.
When we reach Santiago, we will get our Compostela in Santiago. The "diploma" issued to pilgrims who have walked at least the final 100km of the Camino on foot. Our name will be printed in Latin. We will get a different color depending on whether we walked for religious reasons or for other reasons (historical).