Lithosphere - Crust
Aesthenosphere - Semi solid Liquid, Upper Mantle
Convection - Semi solid liquid is heated and rises to the surface and cools, and sinks again. This is convection.

Plate Tectonics - A theory that the earths crust is made of plates
If one plate rides on top of another and one sinks into the semi solid liquid below and is destroyed. Folding - When rocks buckle. Anticline - Rocks bending up. Syncline - Rocks bend down. Fault - Break in the earths crust.