📝 Requirements Engineering

📝 Requirements Engineering (Functional vs Non-Functional) 

         # Functional Requirements                                               

          • What system should do       

          • User actions / behavior     

          • Examples: Login, Add to Cart, Payment

           

         # Non-Functional Requirements                                     

         • How system should behave                                         

         • Quality / Performance                                                  

         • Examples: Load time < 2s, Handle 1000 users, Data security

🔹 What is Requirements Engineering?

Requirements Engineering (RE) ek process hai jisme software ke needs aur expectations ko identify, document, aur validate kiya jata hai.

• Ye software development ka pehla aur crucial step hai.

• Agar requirements clear nahi hongi → software failure ya customer dissatisfaction ho sakta hai.

---

🔹 Types of Requirements

1️⃣ Functional Requirements

• Software ko kya kaam karna hai ye specify karte hain.

• Directly user ke actions ya system behavior se related hote hain.

• Example:

  • User login kar sake.

  • Product cart me add kar sake.

  • Payment process ho jaye.

• Question: “System kya karega?” → Functional requirement ka jawab hai.

---

2️⃣ Non-Functional Requirements (NFR)

• Software kaise kaam karega ye specify karte hain.

• Quality, performance, usability, security, scalability se related hote hain.

• Example:

  • App 2 seconds me load ho.

  • System 1000 concurrent users handle kare.

  • Data encrypted ho (Security).

• Question: “System ka quality aur behavior kaisa hoga?” → NFR ka jawab hai.

---

🔹 Comparison Table

Feature	Functional Requirement	Non-Functional Requirement
Definition	Kya system karega	Kaise system karega
Focus	Behavior / Actions	Quality / Performance
Examples	Login, Add to Cart, Payment	Response Time, Security, Reliability
Testing	Unit / Integration Testing	Performance / Load / Security Testing

---

🔹 Importance

• Clear requirements → Better design

• Avoid ambiguity → Less rework & cost saving

• Helps in Testing and Validation