SDLC Models Explained
The different ways teams plan and build software.
What is SDLC?
The Software Development Life Cycle (SDLC) is a structured process for planning, creating, testing, and deploying software â covering requirement gathering, design, implementation, testing, deployment, and maintenance.
Waterfall Model
A linear, sequential model where each phase must complete before the next begins. Simple to manage, but inflexible â changes discovered late (like in testing) are expensive to fix.
Agile Model
Software is built in small, iterative cycles called sprints, with continuous feedback and adaptation. This handles changing requirements much better than Waterfall and is the most widely used approach today.
đ Real-World Use
Most modern tech companies (Google, Amazon, startups) use Agile with 2-week sprints, releasing small updates constantly. Government or safety-critical projects (defense, aviation software) sometimes still prefer Waterfall for its strict documentation and predictability.
đĄ Pro Tip
When asked 'which SDLC model is best', the smart answer connects it to context: Agile for fast-changing startup products, Waterfall for well-defined, unchanging requirements like a fixed government contract.
đ§Ē Quick Self-Test
Check what you just learned â no pressure, just practice.
1. Which SDLC model is linear and sequential?
2. What is a 'sprint' in Agile?