Software Development Life Cycle
The Software Development Life Cycle (SDLC) is a framework that defines the process used to build software from initial concept to final deployment and maintenance. It provides a structured approach that ensures quality and efficiency.
The SDLC Phases
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| SDLC PHASES |
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| 1. Planning |
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| 2. Requirements Analysis |
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| 3. Design |
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| v |
| 4. Implementation (Coding) |
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| v |
| 5. Testing |
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| v |
| 6. Deployment |
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| 7. Maintenance |
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Phase Details
Planning: Define project scope, resources, timeline, and feasibility. This is where you determine if the project is worth pursuing.
Requirements: Gather what the system must do. Interview stakeholders, analyze existing systems, and document functional and non-functional requirements.
Design: Create the architecture, data models, interfaces, and component designs. This is the blueprint for development.
Implementation: Write the actual code following the design specifications. Developers work in sprints or iterations depending on the methodology.
Testing: Verify the software works as intended. Find and fix bugs before release.
Deployment: Release the software to production environments for users.
Maintenance: Fix bugs, add features, and keep the software running smoothly.
SDLC Models
Different project types benefit from different SDLC models. The Waterfall model follows phases sequentially, while Agile breaks work into iterative cycles. We'll explore these in detail in the Software Process Models lesson.
Waterfall vs Agile:
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WATERFALL: AGILE:
Requirements -----> Sprint 1 -> Sprint 2 -> Sprint 3
Design ---------> | Plan | Plan | Plan
Code -----------> | Build | Build | Build
Test -----------> | Test | Test | Test
Deploy --------> | Release | Release | Release
Feedback --> Feedback --> Feedback
Key Takeaways
- The SDLC provides a structured approach to software development
- Each phase has specific goals and deliverables
- Different SDLC models suit different project needs
- Understanding the SDLC helps teams deliver quality software consistently