Features, Requirements, Use Cases, and User Stories – What’s the Difference?

Glossary

Agile A modern software development approach focused on short, iterative cycles and continuous improvement. User stories come from this context.

Feature A broad, user-visible capability that the system provides.

Requirement A precise condition or behavior the system must meet.

Use Case A structured description of how a user interacts with the system through a sequence of steps to achieve a goal.

User Story A short, value-focused description of a user need written from the user’s perspective.

---

When you start building software, you’ll hear people throw around words like feature, requirement, use case, and user story.
They’re all about describing what a system should do, but they look at it from slightly different angles.

Features – The Big Headline Items

Info

A feature is a high-level capability of the system — something the product can do.

Think of it like the chapter title in a book: short, clear, and exciting.

Example

• Dark mode for the app
• Export data to CSV
• Friend-to-friend money transfer

Features don’t go into step-by-step details — they just describe the “what”, not the “how”.

Requirements – The “Must-Haves”

Info

A requirement is a clear statement of something the system must do (or how it must behave).

They can be functional (about actions) or non-functional (about qualities).

Example

• The system must allow a user to reset their password via email verification.
• The website must load in under 2 seconds on a 4G connection.

Tip

In traditional software engineering, every feature is usually backed by multiple requirements that make it real and testable.

Use Cases – The Story of Interaction

Info

A use case tells a story: how a person (or system) interacts with your product to achieve a goal.

It has an actor (the one doing something) and a flow (the steps).

Example

Actor: Bank customer
Goal: Withdraw cash
Flow:

1. Insert card into ATM
2. Enter PIN
3. Choose “Withdraw”
4. Select amount
5. Take cash and receipt

Use cases help you think about every step needed — and also what happens if something goes wrong.

User Stories – The Quick, Human Version

Info

A user story is a short sentence that captures who wants something, what they want, and why.

It’s super common in Agile teams.

Format:
As a [role], I want [goal] so that [reason].

Example

• As a student, I want to save my work automatically so that I don’t lose progress if my laptop crashes.
• As a gamer, I want to customize my character so that I can make it feel unique.

Tip

User stories are easy to read, even for non-technical people. They focus on value, not on technical details.

Acceptance Criteria – Proving It Works

Once you have a user story, you need a checklist to prove it’s done.
That’s where Given/When/Then comes in.

Format:

Given [starting situation]
When [action happens]
Then [expected outcome]

Example

Given I have items in my cart
When I click "Checkout"
Then I should be taken to the payment page

How They Fit Together

Tip

Think of it like zoom levels on a map:

• Feature → The whole city ("Messaging system")
• Requirement → Specific street ("Must support sending text, images, and files")
• Use case → Walking path ("User sends an image to a friend")
• User story → Postcard summary ("As a user, I want to send pictures so my friends can see what I’m doing").

Why This Matters

Danger

Without clear definitions, your team might build the wrong thing — or build it in a way that nobody wanted.

Knowing the difference helps you:

• Communicate better with your team
• Plan your work in logical steps
• Make sure you’re delivering value to the user