Pixel aspect ratio:Pixel ratio (Pixel aspect ratio - often abbreviated PAR) is a mathematical ratio that describes how the width of a pixel in a digital image compares to the height of that pixel.
Resolution:Image resolution can be measured in various ways. Basically, resolution quantifies how close lines can be to each other and still be visibly resolved. Resolution units can be tied to physical sizes (e.g. lines per mm, lines per inch), to the overall size of a picture (lines per picture height, also known simply as lines, TV lines, or TVL), or to angular subtenant. Line pairs are often used instead of lines; a line pair comprises a dark line and an adjacent light line.
Display PPI:PPI is the acronym from Pixels Per Inch. It is a unit of measure used to quantify the number of pixels found on a square inch surface. To get a clear idea of what it means, imagine a square inch that is divided and organized in a grid of cells. Each and every cell in that grid has a pixel inside. The number of cells inside the grid, also known as pixels, tells you the PPI.