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📋Software TestingBeginner

Software Testing Life Cycle (STLC)

📌 Definition:

STLC is a structured process that defines the phases of testing activities from start to finish.

📖 Detailed Explanation:

STLC is similar to SDLC but focuses specifically on testing activities. Each phase has clear entry and exit criteria, defined deliverables, and responsibilities. Following STLC ensures testing is systematic, traceable, and repeatable across projects.

📎 Phases:
Requirement Analysis
Description:

Understand business requirements, acceptance criteria, and scope of testing

Activities:
  • Review requirement documents with stakeholders
  • Identify testable requirements
  • Mark unclear or missing requirements
  • Create a traceability matrix to map requirements to test cases
Deliverable:

Requirements Test Plan, Traceability Matrix

Example:

For e-commerce app: Identify requirements like 'User can add items to cart', 'Apply discount code', 'Complete payment'. These become testable requirements.

Test Planning
Description:

Define testing strategy, scope, timeline, resources, and budget

Activities:
  • Determine testing types needed (functional, performance, security)
  • Identify testing tools and technology
  • Allocate testing team and schedule
  • Define entry and exit criteria
  • Plan test environment and data requirements
Deliverable:

Test Plan document

Example:

Decide: We'll do manual functional testing (2 testers, 4 weeks), automated regression testing, and performance testing on 3 browsers.

Test Case Design
Description:

Create detailed test cases covering positive, negative, and edge cases

Activities:
  • Write test case steps with expected results
  • Create test data sets
  • Design scenarios covering all requirements
  • Review and get approval from QA lead
Deliverable:

Test Cases document (100+ pages typically)

Example:

Test Case: Login with invalid credentials. Steps: 1) Open login page 2) Enter invalid email 3) Enter wrong password 4) Click login. Expected: Error message 'Invalid credentials'. Actual: [To be filled during execution]

Test Environment Setup
Description:

Prepare hardware, software, and data needed for testing

Activities:
  • Install OS, browsers, databases
  • Configure network and security settings
  • Load test data and master data
  • Prepare mock services and APIs
  • Verify environment matches production configuration
Deliverable:

Test environment ready and verified

Example:

Set up 3 test servers with Windows/Linux/Mac, browsers (Chrome, Firefox, Safari), test database with 10,000 user records.

Test Execution
Description:

Run test cases and log results

Activities:
  • Execute test cases systematically
  • Log actual results
  • Compare actual vs expected results
  • Report defects for failures
  • Re-test after fixes (regression testing)
  • Track progress with metrics
Deliverable:

Test Execution Report, Defect Report, Test Progress Dashboard

Example:

Day 1: Execute 50 test cases. 45 passed, 5 failed. Created 5 bugs. Day 2: Bugs fixed, re-test. All 50 passed.

Test Closure
Description:

Analyze overall testing effectiveness and close testing activities

Activities:
  • Verify all planned tests were executed
  • Calculate test coverage and metrics
  • Document lessons learned
  • Archive test cases and results
  • Get sign-off from stakeholders
  • Identify improvements for next release
Deliverable:

Test Closure Report, Lessons Learned document

Example:

Coverage: 95% of requirements tested, 98% of code covered, 50 defects found and fixed. Quality ready for production.

🎯 Scenario-Based Interview Question:

You have 10 days to test a new payment module. Walk me through your STLC activities day by day.

💡 Quick Tip:

📌 STLC ensures systematic, traceable, and repeatable testing. Skipping phases causes chaos.

💡 Interview Focus:

Interviewers want to see candidates understand why each phase is critical and cannot be skipped.

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