Castings can be produced either in permanent metal moulds or in expendable refractory ones. Major part of the foundry industry output represents the castings made in refractory expendable moulds.
Moulding methods range from the manual moulding techniques up to the machine moulding ones. Owing to the low productivity and strenuous labour, manual moulding is currently used only to a limited extent. On the contrary, enabling the moulds to be produced at high rates, machine moulding is characterized by high productivity, higher accuracy and no need of a highly qualified labour force. The most modern foundries for mass production use the automatic moulding lines in which a high degree of mechanized operations and automation is achieved. The entire casting process there is mechanized and automated; not just the moulding operation itself, as is the case of individual moulding machines.
According to the class of the binder and the way of achieving the final strength of the moulding aggregate, individual methods of the mould and cores production can be divided into four generations.
| Moulding Methods of | The Way of Achieving Final Strength | Basic Composition of the Moulding Aggregate |
| 1st Generation | Mechanical compaction | Base aggregate, clay binder and water |
| 2nd Generation | Hardening by chemical change of the binder | Base aggregate, chemical binders |
| 3rd Generation | Physical binding between the aggregate grains | Base aggregate, no binder (sometimes water) |
| 4th Generation | Aggregate grains are bonded with biological substances | Base aggregate, binder of living organisms (e.g. bacteria) |