SPI interface on Arduino Uno and Arduino Sensor Shield

ATMega328P supports 1 SPI Master/Slave interface. We can connect various peripherals like Memory, ADC to this interface. SPI interface is supported on below pins in the Arduino Board.

We can see that Arduino Uno board also supports ICSP programming over the SPI interface and for this there is an ICSP header on the board. Below image shows the ICSP header highlighted.

The same SPI pins are routed to the Arduino Sensor Shield board and are covered under the SD Interface connector.