IPC (Inter-Process Communication)
IPC is the broad concept — it refers to any mechanism that allows separate processes to exchange data. It’s not a specific technology but rather an umbrella term covering many approaches: shared memory, message queues, pipes, signals, and sockets. Both Unix sockets, TCP and UDP can be used as IPC mechanisms.
IPC (narrow/common usage)
Local-only mechanisms (Unix sockets, pipes, shared memory)
TCP & UDP
Network protocols that can do IPC, but are designed for cross-machine use