it is an integrated circuit that connects all the components of a computer, they most often contains the central processing unit, memory unit and other IO device interfaces in the chip
the above mentioned image is from the raspberry pi
a SOC integrates the microcontroller/microprocessor with the other peripherals like WiFi, bluetooth and cellular network modems together
- SoC consumes less power than a multichip architecture and due to this the replaceabilty of the components is also reduced