The third section of the Mass is called the Liturgy of the Eucharist, of which the Offertory is the first part. This part is also known as the Preparation of the Altar and Gifts. This is when the collection is taken, we usually sing a song together, the gifts (bread, wine, and other gifts) are brought forward, and the table is set for Communion.
From Papa Francis: Sharing
Pope Francis spoke on how we are called to share all we are and have: “It is important not to turn in on ourselves, burying our own talent, our spiritual, intellectual, and material riches, everything that the Lord has given us; but, rather to open ourselves, to be supportive, to be attentive to others. Set your stakes on great ideals, the ideals that enlarge the heart, the ideals of service that make your talents fruitful. Life is not given to us to be jealously guarded for ourselves, but is given to us so that we may give it in turn.” What might we be burying instead of sharing?