A cement is a finely-powdered substance which possesses strong adhesive qualities when combined with water. Gypsum plaster, common lime, hydraulic limes, puzzolana, natural and Portland cements are a few of the materials which are used for cementing purposes, with Portland cement being the most important in construction.
Cement was first invented by the Egyptians, and later reinvented by the Greeks and Babylonians, who made their mortar out of lime, much harder than the Roman mortars. Later, the Romans found cement and concrete, puzzolana to be exact, to be an excelent building material. When the Roman empire fell apart, the idea of cement was lost. But around 1700 - 1900, cement and concrete were slowly reinvented.
Cement is also the name of Chuck Mosley's post Faith No More band. Additionally, CEMENT is an acronym for Computer Enhanced Multiple Exposure Numerical Technique in which multiple pictures of the same subject matter are "cemented" together to attain increased picture resolution or for artistic visual lightspaces.