Not to be confused with Socket on Chip (SoC). That is a term used to describe a component in a computer.
A Security Operations Center, or SOC is a an evolved form of the Network Operations Center (NOC).
A NOC houses certified technicians that will provide your company with vital information about what is happening in your network (of devices), and attempt to fix whatever that is going wrong.
A SOC takes this further with investigation of the IT issue that is affecting the network and takes steps to make sure that it will not happen again. A SOC not only takes on the tasks of the NOC, but also has its main focus on the cyber security of the company that it is assisting.
A SOC not only consists of certified technicians, but also cyber security experts.