Answer:
Line defects are produced when a complete row of atoms have anomalous localization respect to perfect crystalline lattice.
The edge dislocation looks like an extra plane of atoms inserted midway through the crystal distorting nearby planes of atoms.
Screw dislocation looks like a crystal cut along a plane and one half is slipped respect to the other by one lattice vector
Mixed dislocation have both screw and edge character.
The surface defects are plane of atoms where determinated crystaline structure of a solid is interrumpted: the surface of a material is a defect, the atoms in the surface have less bonds that others atoms, and the grain boundaries are other kind of surface defects since orientation of a plane of atoms is different for each adjoining grain.
