Iterative and Incremental development is any combination of both
iterative design or
iterative method and
incremental build model for software development. The combination is of long standing and has been widely suggested for large development efforts. For example, the 1985 DOD-STD-2167 mentions (in section 4.1.2): "During software development, more than one iteration of the software development cycle may be in progress at the same time." and "This process may be described as an 'evolutionary acquisition' or 'incremental build' approach." The relationship between iterations and increments is determined by the overall
software development methodology and
software development process. The exact number and nature of the particular incremental builds and what is iterated will be specific to each individual development effort.