Modularity

Modularity, in systems engineering, is the ability for a system or product to be broken into groups of parts that have an entity outside of the system itself. Webster’s dictionary defines the noun ‘‘module’’ as: Modularity is one of several factors that are used in the design phase of systems engineering. The objective of modularity is to increase the ease of repairability and maintenance of a given system, decrease the downtime of the system, simplify the design of the system, reduce costs (via precompiled modules), and increase the ability of the system to adapt to new changes (with the ability to upgrade modules, rather than the entire system at large).
 * : one of a set of parts that can be connected or combined to build or complete something
 * : a part of a computer or computer program that does a particular job
 * : a part of a space vehicle that can work alone

"In engineering design, modularity can be exploited at the early stages of product development to significantly reduce development effort (i.e., time and cost)."