If a liquid is in contact with a solid, then there are two possibilities: 1) the molecules of the liquid are attracted to each other more strongly than to the molecules of the solid. As a result, the forces of attraction between the molecules of the liquid collect it into a droplet. This is how mercury behaves on glass, water on paraffin or “oily” surfaces. In this case, it is said that the liquid does not wet the surface; 2) molecules of a liquid are attracted to each other weaker than to molecules of a solid. As a result, the liquid tends to press against the surface and spreads over it. This is how mercury behaves on a zinc plate, water on clean glass or wood. In this case, it is said that the liquid wets the surface.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.