Formwork (forms)
The temporary molds that hold concrete in place until it can support itself. Forms control dimensions, alignment, and surface appearance.
What does formwork (forms) mean?
Formwork must resist the substantial fluid pressure of fresh concrete, which increases with pour rate and decreases as the concrete stiffens. A blowout is usually a bracing failure rather than a material failure. Form quality directly determines finished appearance on exposed work, since the form face is imprinted into the concrete.
In practice
On residential flatwork the forms are usually staked two-by lumber; on walls they are engineered panel systems with ties on a calculated spacing.