What does pre-stressed concrete mean?

thanks for the invitation

Pre-stressed concrete is a composite of concrete and steel combination high resistance as they already have anti-stress and the negative impact of the pressures resulting from the loads acting on the structural element which raises at the end of their ability to withstand dead and live loads that affect it. Already it emphasizes the reduction of bending and cracks that can occur in a fraction of concrete and can be obtained strain Iron own machine used in concrete work, which covers a wide sea and buildings with control in the thickness of its sector be practical as well as benefit