what is the different between Image Resolution and Line Screen
Spatial resolution, typically some number of dots per inch, corresponds roughly to the ability to render graphic detail. On a computer screen, it’s the number of pixels per linear inch (ppi); on an output device, it’s the number of dots printed in a linear inch (dpi); on a scanner, it’s the number of pixels sampled per linear inch of the scanned image. The resolution of a raster image depends on the size it’s printed as well as on the pixel dimensions of the file. Pixel dimensions determine file size; and, as a practical matter, file size is related to storage and processing efficiencies.