Paint is a liquid or liquefiable composition which after application to a substrate in a thin layer is converted to a dense and thick solid film. It is most commonly used to protect, color or provide texture to objects.VARNISH
Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent. It is a transparent, hard, protective finish or film principally used in wood finishing. Its finishes are usually glossy but may be designed to produce satin or semi-gloss sheens by the addition of "flatting" agents.
DIFFERENCE BETWEEN PAINTS AND VARNISHES:
Varnish has little or no colour, is transparent, and has no added pigment, as opposed to paints, which contain pigment and generally range from opaque to translucent. Varnishes are also applied over wood stains as a final step to achieve a film for gloss and protection.
After being applied, the film-forming substances in varnishes either harden directly, as soon as the solvent has fully evaporated, or harden after evaporation of the solvent through certain curing processes, primarily because of chemical reaction between oils and oxygen from the air or between components of the varnish.
Paints have a long range of colours, they may or may not be transparent and have added pigments and binders. They can be applied on any surface. When applied they form a semi solid thin film on that surface and harden after some time and thus protect the surface. Paints are also used to give texture to a surface and they may or may not be glossy.