This book is devoted to thin-walled structural elements with initial stresses. Distinguish the following basic thin-walled structural elements: plates, shells, membranes, rods, beams, and strings. The behavior of plates, shells, rods, and beams is determined equally by initial stresses in the structural element and the elastic characteristics of the structural element. The behavior of membranes and strings is determined only by initial stresses in the structural element. In this book, we will consider plates and beams. Those interested in non-uniform membranes and strings can find some information in Kolpakov (2004).