Perfect — this is a high-yield OA topic. Below is everything you need to know about Software Development Models, trimmed to exactly what gets asked in QC / Software Engineering OAs (MCQs + short theory).

Think of this as a one-shot revision sheet.

✅ Important Software Development Models (For OA)

🔥 MOST IMPORTANT (Must-Know 100%)

1️⃣ Waterfall Model

📌 Most commonly asked model in OAs

Flow (linear):

Requirements → Design → Implementation → Testing → Deployment → Maintenance

Key Points:

• Sequential (next phase starts only after previous ends)
• Easy to understand & manage
• Works well when requirements are clear & fixed

Advantages:

• Simple & structured
• Clear documentation

Disadvantages (VERY IMPORTANT):

• No flexibility
• Testing happens late
• Changes are expensive