The 74HC595 is an 8 bit serial in, parallel out shift register.

TestShiftOut



TestBitBangSlow



TestBitBangFast



TestSPI





Program 1 000 000 updates Updates/sec
TestShiftOut
138.013
7 246
TestBitBangSlow
122.482
8 164
TestBitBangFast
12.637
79 133
TestSPI
2.702
370 096