developing systems: The systems analysis phase and the design phase.

Together, the two provide a comprehensive view of development: system analysis is the top of the funnel where all the information is gathered, sorted, and evaluated, but the design is the narrow part of the funnel, where that information is combined and reduced to program specifications for the developers.

The systems analysis phase of the SDLC is concerned with identifying a system‟s functional requirements — in other words, what the system should do. In systems analysis, you focus on identifying what data and information are required in the system and what processes the system must support, through the gap analysis determined by the comparison of current and future states. This process focuses on analyzing the needs of the system.

Three sub-phases make up the analysis phase:

1. Requirements gathering (Topic 4.2)
2. Requirements structuring process (Topics 4.3, 4.4, 4.5, and 4.6)
3. Generation and selection of alternative design strategies (Topic 4.7)

Deciding on the best design and design strategy is the goal of the system design phase. The design strategy includes various activities, such as file and database design, program design, network design, platform design, and user interface design.

Development projects must first be understood in terms of their size and nature, to determine which methodology (such as SDLC, RAD or agile) will best suit them. This is part of the analysis phase, and one where IS plays a key role.

A system is only as good as its requirements statement. The cost of fixing errors increases dramatically the further