Course IntroductionLesson 6 of 6

Use Cases for All Tools

Theory is useful — but seeing a tool in action makes it stick. Each section below shows three real scenarios for one Claude tool, with examples of exactly what you would type and what you get back.

💬

Claude Chat

Open claude.ai in any browser. No installation needed. Best for writing, explaining, and quick answers.

1

You need to write a professional email declining a meeting

claude.ai
Write a short, polite email declining a meeting request. The meeting is about a project I am not involved in.
C
Subject: Re: Meeting Request Hi [Name], Thank you for the invitation. Unfortunately, as I'm not directly involved in this project, I wouldn't be the right person to attend. I'd suggest looping in [relevant colleague] instead. Best regards, [Your name]

Claude writes a ready-to-send email. You just fill in the names.

2

You need to understand a confusing concept quickly

claude.ai
Explain compound interest in plain English with one simple example.
C
Compound interest means you earn interest on your interest, not just your original amount. Example: you put £1,000 in a savings account at 10% per year. After year 1 you have £1,100. In year 2 you earn 10% of £1,100 (not £1,000), so you get £110 — totalling £1,210. The longer you leave it, the faster it grows.

Add "explain it like I'm 10" or "explain it like I'm an economist" to adjust the level.

3

You have a long article and need only the key points

claude.ai
Summarise this article in 5 bullet points. [paste article text here]
C
⬢ The study covered 10,000 participants across 12 countries. ⬢ Sleep deprivation of more than 6 hours increases error rates by 40%. ⬢ Short naps (20 min) partially offset the deficit. ⬢ Performance declined most steeply after day 3 of poor sleep. ⬢ Researchers recommend 7–9 hours as the optimal range for adults.

Works with any text — reports, research papers, meeting notes, or web articles.

When to use Chat: Any writing, explanation, or Q&A task that you can describe in a message. No files on your computer, no code running.
💻

Claude Code

Run claude in your terminal inside any project folder. Claude reads your actual files and edits them directly.

1

You want to add input validation to an existing form

Terminal — Claude Code
# Inside your project folder
$ claude
> What would you like me to do?
You: Add validation to the contact form in contact.js — email must be valid, name must be at least 2 characters
• Reading contact.js⬦
• Identifying form submit handler⬦
• Writing validation logic⬦
• Updating contact.js⬦
✓ Validation added. Email regex check + name length check on lines 18–26. No other files changed.

Claude edits the real file on your machine. You do not copy-paste anything.

2

You have a bug but don't know where it is

Terminal — Claude Code
# Inside your project folder
$ claude
> What would you like me to do?
You: The checkout total is sometimes showing as NaN. Find the bug and fix it.
• Scanning cart.js, checkout.js, pricing.js⬦
• Found issue: parseFloat() called on undefined in pricing.js line 44⬦
• Adding null check before parseFloat()⬦
✓ Bug fixed in pricing.js line 44. Added guard: if (!price) return 0.

Describe the symptom — Claude finds the root cause across multiple files.

3

You need tests for a function you just wrote

Terminal — Claude Code
# Inside your project folder
$ claude
> What would you like me to do?
You: Write unit tests for the calculateDiscount function in utils.js using Jest
• Reading utils.js⬦
• Analysing calculateDiscount logic and edge cases⬦
• Creating utils.test.js⬦
✓ Created utils.test.js with 6 test cases — covers normal input, zero discount, 100% discount, and negative values.

Claude writes tests for your existing code — you just run them.

When to use Claude Code: Any task where you need changes made inside a real project on your computer — adding features, fixing bugs, writing tests, or refactoring code.
⚡

Skills & Plugins

Enable plugins inside claude.ai with one click. Each plugin gives Claude a new ability — live web search, file reading, data analysis, and more.

1

You need the latest information Claude's training doesn't cover

claude.ai
🔍 Web Search active
What is the current version of React and when was it released?
C
Searching the web⬦
React 19 was released on December 5, 2024. Key new features include Server Components, the new use() hook, and improved hydration error messages. You can install it with npm install react@19.

Without Web Search, Claude's answer would be limited to its training cutoff. The plugin removes that limitation.

2

You have a PDF report and want key insights extracted

claude.ai
📄 Document Reader active
Here is our Q1 sales report (PDF). What are the top 3 products by revenue?
C
Reading uploaded document⬦
Based on the Q1 report: 1. Product A — £142,000 (34% of total) 2. Product B — £98,500 (23%) 3. Product C — £76,200 (18%) These three account for 75% of total Q1 revenue.

Upload any PDF, Word doc, or spreadsheet — Claude reads it and answers your questions about it.

3

You need a quiz generated from your course material

claude.ai
📝 Quiz Builder active
Create a 5-question multiple-choice quiz based on the lesson I just uploaded about photosynthesis.
C
Processing document — generating quiz⬦
Quiz ready: 1. What is the primary energy source for photosynthesis? a) Water b) Carbon dioxide c) Sunlight ✓ d) Oxygen 2. Which gas is released as a by-product? a) Carbon dioxide b) Nitrogen c) Hydrogen d) Oxygen ✓ [3 more questions generated⬦]

Specialist plugins like Quiz Builder turn Claude into a domain-specific tool for teachers, trainers, and content creators.

When to use Skills & Plugins: When you need live data, file analysis, or a specialist workflow that standard Chat cannot do on its own.
🤝

Claude Cowork

A desktop app where Claude can take action on your computer — opening files, controlling your browser, filling forms, and running multi-step tasks without you doing each step manually.

1

You have 30 product images to rename following a naming convention

Claude Cowork
Task running

Your instruction: “Rename all images in /products folder: format should be product-[id]-[colour].jpg. The IDs and colours are in products.csv.”

✓Opening /products folder
✓Reading products.csv — found 30 rows
✓Renaming images (30/30)⬦
✓Verifying file names
✓ All 30 images renamed. 0 errors. Original names backed up in /products/backup.

A task that would take 15 minutes manually takes 20 seconds with Cowork.

2

You need to fill in a job application form from your CV data

Claude Cowork
Task running

Your instruction: “Open the application form at careers.example.com and fill it in using the details in my-cv.pdf”

✓Reading my-cv.pdf
✓Opening careers.example.com in browser
•Filling in name, email, experience fields⬦
○Upload CV attachment
✓ Form filled in. Please review before submitting — click Submit when ready.

Cowork navigates the browser and fills the form. You review and submit with one click.

3

You need a weekly competitor pricing report without doing it manually

Claude Cowork
Task running

Your instruction: “Visit the pricing pages of Competitor A, B, and C. Extract their plan names and prices. Save a comparison table to pricing-report.xlsx.”

✓Visiting competitor-a.com/pricing⬦
✓Visiting competitor-b.com/pricing⬦
✓Visiting competitor-c.com/pricing⬦
✓Writing pricing-report.xlsx
✓ Saved pricing-report.xlsx — 3 competitors, 9 plans, all current prices as of today.

Run this every Monday morning. Cowork handles the entire research and data-collection workflow.

When to use Cowork: Any task where you would normally have to click through multiple steps yourself — file operations, browser tasks, form filling, or multi-source data gathering.

Quick Reference

Match your task to the right tool at a glance.

Task typeBest tool
Write an email, summary, or document💬 Chat
Explain a concept or answer a question💬 Chat
Add a feature or fix a bug in your codebase💻 Code
Write tests or refactor existing code💻 Code
Get up-to-date info from the web⚡ Web Search plugin
Analyse an uploaded PDF or spreadsheet⚡ Document plugin
Rename, move, or organise files in bulk🤝 Cowork
Fill forms or navigate websites automatically🤝 Cowork
Compile a research report from multiple websites🤝 Cowork

Key Takeaways

  • 💬Chat handles writing, explaining, and Q&A entirely in the browser — no installation, no setup.
  • 💻Claude Code works inside your actual project — describe the task, and Claude edits the real files.
  • ⚡Plugins break Claude's default limits — add web search, file reading, or specialist workflows with one click.
  • 🤝Cowork eliminates manual steps — it can click, fill, read, and save across multiple apps on your behalf.
  • 🎯Start every task by asking: 'Is this a conversation, a code edit, a data task, or a multi-step action?' That answer points to your tool.

What's Next

You've seen what's possible. The next lesson helps you decide which Claude tool to reach for depending on the task.