Any electronic or electromechanical unit of equipment. A machine is always hardware; however, "engine" may refer to hardware or software. See
engine.
The term can sound old fashioned or high-tech. For example, when an older generation is subjected to a new technology, a new device is often called a machine. In times past, even a microphone was called a machine. However, "machine language" is 21st century terminology, and "machine architecture," "machine tools" and other "machine" terminology is not at all antiquated.