Formwork is a mold or open box, like a container in which fresh concrete is poured and compacted. When the concrete is set, the formwork is removed and a solid mass is produced in the form of the interior face of the formwork. The top of the formwork is normally left open.Falsework is the necessary support system that holds the formwork in the correct positionFormwork for concrete structural should be

1- Strong enough to resist the pressure or the weight of the fresh concrete plus any constructional live loads.

2- Rigid enough to retain the shape without undue deformation.

3- Economical in terms of the total cost of the forms and the concrete surface finishing when required.

4- Sufficiently watertight to avoid leakage at the joints.Formwork materials

Formwork intended to form part of the permanent structure will generally be steel or concrete, Temporary formwork designed to be struck and reused may be made from any economic and easily worked material, timber, steel and GRC/GRP being the most common.

Formwork materials can be classified as:

1- Timber Formwork

2- Metal Formwork

3- Plastic Formwork

4- Insulating concrete form or insulated concrete form (ICF)