All solid bodies consist of uncountable quantity of molecules and atoms - why these bodies do not break up to components? What holds all these particles together especially as all these molecules are not connected densely among themselves, and are in the constant chaotic movement at a certain distance from each other?
Solid bodies keep the form thanks to force of a mutual attraction which constantly exists between all molecules making solid bodies. This force works from each molecule of substance which attracts to itself each next molecule and itself is mutually attracted by them. Force of an attraction of a single molecule it is insignificant it is small, but the integrated force of billions of molecules is rather strong that the subject existed as a unit and did not break up to parts. In different substances attraction force between molecules is not identical therefore some materials break it is easier (paper), and some in which force of an intermolecular attraction works more intensively it is difficult to destroy (steel). However this intermolecular force acts only on very small distance between the next molecules, comparable to the sizes of elementary particles. If the distance though exceeds certain sizes a little - these forces of an attraction sharply decrease. If to break any subject, intermolecular interactions vanish completely at distance already a little more than 0.000001 cm between particles. The broken parts of some solid bodies (a tree, metal at usual temperatures, ceramics, plastic, etc.) cannot be connected together that is generally connected with rigid intermolecular structure of substance. By comparison of parts of such objects only very few molecules enter interaction at the level of attraction force. The divided parts of objects from other substances (plasticine, dough) can be reunited again since by their comparison the most part of the molecules and atoms which are not connected by rigid structure will read to get to a zone of a mutual attraction, and molecules begin to interact among themselves, attracting each other and restoring integrity of the subject divided earlier. If to squeeze a body - intermolecular intervals decrease, and here intermolecular forces of mutual pushing away which interfere with "adhesion" of molecules already begin to work.