Functional vs non-functional requirements in Software Engineering - Hands-On Comparison

Understanding Functional vs Non-Functional Requirements

📖 Scenario: You are part of a software development team planning a new mobile app for a local library. To make sure the app meets users' needs, you need to clearly list what the app should do and how well it should perform.

🎯 Goal: Build a clear list that separates functional requirements (what the app must do) from non-functional requirements (how the app should behave or perform).

📋 What You'll Learn

Create a dictionary called functional_requirements with exactly these entries: 'User login': 'Allow users to log in with email and password', 'Search books': 'Enable searching books by title, author, or ISBN', 'Borrow books': 'Allow users to borrow available books'

Create a dictionary called non_functional_requirements with exactly these entries: 'Performance': 'App should load pages within 2 seconds', 'Security': 'User data must be encrypted', 'Usability': 'App must be easy to navigate for all ages'

Create a list called all_requirements that combines the keys from both dictionaries in this order: functional requirements first, then non-functional requirements

Add a final statement as a string variable called summary that explains the difference between functional and non-functional requirements in one clear sentence

💡 Why This Matters

🌍 Real World

Software teams use functional and non-functional requirements to plan and build software that meets user needs and quality standards.

💼 Career

Understanding these requirements is essential for roles like business analysts, project managers, and software developers to ensure successful software delivery.

1

Create functional requirements dictionary

Create a dictionary called functional_requirements with these exact entries: 'User login': 'Allow users to log in with email and password', 'Search books': 'Enable searching books by title, author, or ISBN', and 'Borrow books': 'Allow users to borrow available books'.

Software Engineering

# Create the functional_requirements dictionary with the specified entries
# Your code here

Need a hint?

Use curly braces {} to create a dictionary with the exact keys and values given.

2

Create non-functional requirements dictionary

Create a dictionary called non_functional_requirements with these exact entries: 'Performance': 'App should load pages within 2 seconds', 'Security': 'User data must be encrypted', and 'Usability': 'App must be easy to navigate for all ages'.

Software Engineering

functional_requirements = {
    'User login': 'Allow users to log in with email and password',
    'Search books': 'Enable searching books by title, author, or ISBN',
    'Borrow books': 'Allow users to borrow available books'
}
# Create the non_functional_requirements dictionary with the specified entries
# Your code here

Need a hint?

Use a dictionary just like in Step 1, but with the new keys and values.

3

Combine requirement keys into a list

Create a list called all_requirements that contains all keys from functional_requirements first, followed by all keys from non_functional_requirements, preserving their order.

Software Engineering

functional_requirements = {
    'User login': 'Allow users to log in with email and password',
    'Search books': 'Enable searching books by title, author, or ISBN',
    'Borrow books': 'Allow users to borrow available books'
}

non_functional_requirements = {
    'Performance': 'App should load pages within 2 seconds',
    'Security': 'User data must be encrypted',
    'Usability': 'App must be easy to navigate for all ages'
}
# Create the all_requirements list combining keys from both dictionaries
# Your code here

Need a hint?

Use list() and .keys() to get keys from each dictionary, then add them together.

4

Add summary explaining the difference

Create a string variable called summary that explains the difference between functional and non-functional requirements in one clear sentence. For example, say that functional requirements describe what the system should do, while non-functional requirements describe how the system should perform or behave.

Software Engineering

functional_requirements = {
    'User login': 'Allow users to log in with email and password',
    'Search books': 'Enable searching books by title, author, or ISBN',
    'Borrow books': 'Allow users to borrow available books'
}

non_functional_requirements = {
    'Performance': 'App should load pages within 2 seconds',
    'Security': 'User data must be encrypted',
    'Usability': 'App must be easy to navigate for all ages'
}

all_requirements = list(functional_requirements.keys()) + list(non_functional_requirements.keys())
# Create the summary string explaining the difference between functional and non-functional requirements
# Your code here

Need a hint?

Write a clear sentence as a string assigned to summary.