In information technology, especially computers and more recently networks, architecture is a term applied to both the process and the outcome of thinking out and specifying the overall structure, logical components, and the logical interrelationships of a computer, its operating system, a network, or other conception. An architecture can be a reference model, such as the Open Systems Interconnection (OSI) reference model, intended as a model for specific product architectures or it can be a specific product architecture, such as that for an Intel Pentium microprocessor or for IBM's OS/390 operating system.
Computer architecture can be divided into five fundamental components: input/output, storage, communication, control, and processing. In practice, each of these components (sometimes called subsystems) is sometimes said to have an architecture, so, as usual, context contributes to usage and meaning.
By comparison, the term design connotes thinking that has less scope than architecture. An architecture is a design, but most designs are not architectures. A single component or a new function has a design that has to fit within the overall architecture.