However, it is usually not possible to achieve all of these goals at once, and the major problem to overcome is that of the varying output resolutions. As of 2016, monitors typically have a resolution of between 102 and 125 pixels per inch, while printers generally have resolutions between 240 and 1440 pixels per inch. In some printers, the horizontal resolution is different from the vertical. This becomes a problem when trying to lay out text; because older output technologies require the spacing between characters to be a whole number of pixels (as rounding errors will cause the same text to require different amounts of space in different resolutions).