dpi stands for dots per inch and is a measure of a printer’s resolution. The higher the number the finer the print will be.
Black colors in print are not all the same. On computer monitors, all blacks will generally appear consistent. But on press, different ink combinations can create a wide range of blacks.
UV coating is basically a compound that is applied to paper wet and then instantly dried by ultraviolet light. Several different types of compounds are used to coat paper, including polyethylene, calcium carbonate and kaolinite.