Resolution is defined by the number of pixels (dots) fitting to one inch and is usually found by the width and height of the image. A high-resolution image contains more pixels per inch, and thus its quality is better. The resolution of files is called dpi (dots per inch). This dpi specification is especially important when printing files. For web use, the most useful resolution is 72 dpi or 96 dpi, because a higher resolution only reduces the size of the files and therefore it’s not advisable. If you plan to print your files, you should select 300 dpi. It should be noted, however, that the image size and the dpi specifications are always dependent on each other. For example, you can change a file that already has a resolution of 72dpi for printing to 300dpi, but this will reduce the size of the image. However, if you keep the size of an image but change the dpi from 72dpi to 300dpi, you will experience significant quality losses. Digital images have different types of resolutions such as pixel resolution, spatial resolution and spectral resolution among others.