Data is sent in 8-bit bytes, most significant bit first, with each byte followed by an ACK/NACK bit.
The master sends the 7-bit unique address of the target slave, followed by a R/W bit (0 for write, 1 for read).
Each slave device has a unique 7-bit (or 10-bit) address, eliminating the need for complex Chip Select (CS) lines used in SPI.
Uses a Serial Data Line ( SDA ) and a Serial Clock Line ( SCL ).