Blink is the basic software you burn to the chip to test the communication between your computer and the chip. It is the very first thing the chip does when it is turned from matter of silicon into a digital brain. The software turns testing led diode on for 1000 milliseconds (1 second), than turns it off and waits another 1000 milliseconds and than repeats.
With blink you can observe the regular changing of time. Light and darkness. 1 and 0. True of false. HIGH of LOW. Opened and closed circuit. Because there are 8 blinking devices you see the basic the 8 bits of the byte. As in any other physical art medium the electronics is imperfect. It cannot keep exactly the same timing of blinking leds. After few hours you can observe that the devices went out of synchronisation. The electronics is imperfect but digital substance stays unchanged and perfectly pure. It represents the digital impossibility to exist in real life in its purity.