Interruptions are one of the great things about microcontrollers, if you want to do something fast, reliable, and simple… well, not exactly simple in a programming language sense perhaps, but really simpler from the hardware perspective point of view. So, the main purpose of interruption is to interrupt your main program cycle and do whatever you want in case of that event (a timer has reached the settled time, a button has been pressed, and so on). Here is the picture from the mikroe ebook (www.mikroe.com), just because they really made quite nice pictures and quite a nice manual by the way.

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