At sometime or another you may run out of pins on your Arduino board and need to extend it with shift registers. ط¢آ With this shift out module which is based onط¢آ 74HC595.ط¢آ The datasheet refers to the 74HC595 as an "8-bit serial-in, serial or parallel-out shift register with output latches; 3-state." In other words, you can use it to control 8 outputs at a time while only taking up a few pins on your microcontroller. You can link multiple registers together to extend your output even more. It canط¢آ also be applies to 51, AVR, PIC and other microcontroller.ط¢آ
It is ideal to work together withInterface Shield for Arduino.