Digital and analog are opposites. Digital means information that is represented as ones and zeros. Analog means information that is represented by signals that vary continuously (that is, including in-between values).
Machine language is the lowest-level programming language; it is directly understood by the computer hardware.
Architecture is an abstraction, a specification of the machine language. It also tells how the processor connects to the memory. It doesn't specify the circuitry; the same architecture can be built as circuitry in many different ways.
An integrated circuit ("IC" or "chip") is a single physical device that contains millions or billions of basic electrical parts. A processor is an IC, but not all processors are IC; there are also special-purpose chips inside a computer.