The 74165 IC is an 8-bit parallel-in serial-out shift register in a DIP-16 package. It allows parallel data loading and serial shifting, making it essential for expanding microcontroller I/O pins, data storage, and digital communication.
The 74HC595 IC is an 8-bit serial-in parallel-out shift register with tri-state outputs, designed to expand microcontroller I/O pins. Packaged in DIP-16/SMD, it features serial-to-parallel conversion, storage register, and 3-state output control, making it ideal for LED displays, drivers, and Arduino projects.