Materials have a measurable elasticity: metals are highly elastic and commonly have high tensile strength, which is the reason why wire cables are so strong.
Materials can have either or both of two forms of strength: strength in compression or strength in tension. Most materials have only one of the two strengths.
Many constructions combine two phases, one material with compressional strength, one material with tensional strength, like reinforced concrete or fibre-glass.
Materials are usually selected to suit the purpose they are to be used for, while two-phase materials combine the advantages of two different materials.
Structures are designed to stay up, and they do so because they distribute stress and load in a way that allows all components to be supported and held.
Arches transfer loads and reduce stress in gap-spanning structures such as bridges, and a cantilever can be used to support a projecting structure.
The aim of the arch is to convert tensional forces to compressional forces, as these are usually easier to manage when people are working in stone.
Stone is a material which can withstand large forces of compression, but it can be shown to be not so strong when it is placed under tension.
Cathedrals and mosques were early structures targeting a large floor space with no columns to block views. This led to a better understanding of engineering.
Large structures like cathedrals, mosques and bridges achieve large spans by transferring the loads to where they can be handled by the materials used.
Any pure material has a characteristic constant density. Density is determined by differences in packing of particles and atomic mass and radius.
Robert Hooke proposed what we now refer to as Hooke's law in these words: The power of any Spring is in the same proportion with the Tension thereof.
In 1744 Leonhard Euler calculated the length of a rod that will buckle under its own weight when stood on one end, indicating that materials have their limits.