Functional vs non-functional requirements in Software Engineering - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the sentence to identify a functional requirement.

Software Engineering

A functional requirement describes what a system [1] to do.

Drag options to blanks, or click blank then click option'

Aneeds

Bshould

Cwants

Ddoes

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing functional requirements with user desires or needs.

Thinking functional requirements describe qualities instead of actions.

A functional requirement specifies what the system does, meaning the actions or tasks it must perform.

2fill in blank

medium

Complete the sentence to identify a non-functional requirement.

Software Engineering

A non-functional requirement defines how well a system [1] its functions.

Drag options to blanks, or click blank then click option'

Aperforms

Bexecutes

Cdelivers

Dimplements

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up non-functional with functional requirements.

Thinking non-functional requirements describe specific system actions.

Non-functional requirements describe how well the system performs its functions, such as speed, reliability, or usability.

3fill in blank

hard

Fix the error in the statement about requirements.

Software Engineering

Functional requirements describe system qualities like [1] and security.

Drag options to blanks, or click blank then click option'

Afeatures

Busability

Cspeed

Dperformance

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing qualities with functions.

Assuming security is a functional requirement.

Functional requirements describe features or specific behaviors, not qualities like speed or security, which are non-functional.

4fill in blank

hard

Fill both blanks to complete the example of functional and non-functional requirements.

Software Engineering

A functional requirement might be 'The system shall [1] user login', while a non-functional requirement might be 'The system shall respond within [2] seconds'.

Drag options to blanks, or click blank then click option'

Aallow

Bauthenticate

C2

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing vague verbs for functional requirements.

Picking unrealistic or incorrect time values for non-functional requirements.

The functional requirement is about authenticating user login (a function). The non-functional requirement specifies a response time of 5 seconds (a quality).

5fill in blank

hard

Fill all three blanks to complete the dictionary comprehension that separates functional and non-functional requirements.

Software Engineering

requirements = {req: type for req, type in req_list if type == '[1]' or type == '[2]' and req != '[3]'}

Drag options to blanks, or click blank then click option'

Afunctional

Bnon-functional

Cperformance

Dsecurity

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up functional and non-functional strings.

Incorrectly excluding the wrong requirement.

This code filters requirements to include only those that are either functional or non-functional, excluding the specific requirement 'performance'.

Practice

1. Which of the following best describes a functional requirement in software engineering?

easy

A. The look and feel of the user interface

B. A measure of how fast the system responds

C. A feature that specifies what the system should do

D. The hardware needed to run the software

Solution

1. Step 1: Understand the definition of functional requirements

   Functional requirements describe specific behaviors or functions the system must perform.

2. Step 2: Match the option to the definition

   A feature that specifies what the system should do states a feature specifying what the system should do, which matches the definition.

3. Final Answer:

   A feature that specifies what the system should do -> Option C

4. Quick Check:

   Functional requirement = What system does [OK]

Hint: Functional = what system does, Non-functional = how it does [OK]

Common Mistakes:

• Confusing functional with non-functional requirements
• Thinking performance is a functional requirement
• Mixing hardware needs with software functions

2. Which of the following is an example of a non-functional requirement?

easy

A. The system must allow users to reset their password

B. The system should respond to user input within 2 seconds

C. The system must save user data to a database

D. The system must support login with username and password

Solution

1. Step 1: Identify non-functional requirements

   Non-functional requirements describe how the system performs, such as speed or reliability.

2. Step 2: Evaluate each option

   The system should respond to user input within 2 seconds specifies response time, which is a performance measure and thus non-functional.

3. Final Answer:

   The system should respond to user input within 2 seconds -> Option B

4. Quick Check:

   Non-functional = performance or behavior [OK]

Hint: Look for speed, usability, or reliability for non-functional [OK]

Common Mistakes:

• Choosing features as non-functional requirements
• Confusing functional actions with performance measures
• Ignoring timing or quality aspects

3. Consider this statement: "The system shall encrypt all user data before saving." What type of requirement is this?

medium

A. Functional requirement

B. Non-functional requirement

C. Neither functional nor non-functional

D. Both functional and non-functional

Solution

1. Step 1: Analyze the statement's action

   Encrypting data is a specific action the system must perform, describing what it does.

2. Step 2: Classify the requirement type

   Since it describes a function (encryption), it is a functional requirement.

3. Final Answer:

   Functional requirement -> Option A

4. Quick Check:

   Encryption = system function = functional [OK]

Hint: If it describes a system action, it's functional [OK]

Common Mistakes:

• Thinking encryption is a performance or quality aspect
• Confusing security features with non-functional requirements
• Selecting 'both' without clear reasoning

4. A software team wrote this requirement: "The system must be user-friendly." What is the main issue with this requirement?

medium

A. It describes a functional requirement incorrectly

B. It is a security requirement

C. It is a hardware requirement, not software

D. It is too vague and not measurable

Solution

1. Step 1: Understand the requirement's nature

   "User-friendly" describes a quality but is subjective and lacks clear criteria.

2. Step 2: Identify the problem

   Requirements must be clear and measurable; this one is vague and cannot be tested easily.

3. Final Answer:

   It is too vague and not measurable -> Option D

4. Quick Check:

   Good requirements = clear + measurable [OK]

Hint: Vague terms mean poor requirements [OK]

Common Mistakes:

• Assuming all non-functional requirements are clear
• Confusing vague qualities with functional features
• Ignoring measurability in requirements

5. A project requires the system to handle 1000 users simultaneously and respond within 1 second. Which combination correctly classifies these requirements?

hard

A. "Handle 1000 users simultaneously" is functional; "respond within 1 second" is non-functional

B. "Handle 1000 users simultaneously" is non-functional; "respond within 1 second" is functional

C. Both are functional requirements

D. Both are non-functional requirements

Solution

1. Step 1: Analyze "handle 1000 users simultaneously"

   This describes a specific system function to support multiple users at once, which is a functional requirement.

2. Step 2: Analyze "respond within 1 second"

   This describes a performance measure, how fast the system reacts, so it is non-functional.

3. Final Answer:

   "Handle 1000 users simultaneously" is functional; "respond within 1 second" is non-functional -> Option A

4. Quick Check:

   Function = what system does; Performance = how system performs [OK]

Hint: Capacity = functional; speed = non-functional [OK]

Common Mistakes:

• Classifying capacity as non-functional
• Mixing performance with system capabilities
• Ignoring the difference between function and quality