claude.ai/ Chat

Introduction to Claude Chat

Claude Chat is the conversational interface at claude.ai — the fastest way to ask questions, write content, analyse files, debug code, and explore ideas in a back-and-forth conversation with Claude.

🌐 Web🖥️ Desktop📱 iOS & AndroidFree to start

What is Claude Chat?

Claude Chat is simply the conversation interface — you type a message, Claude responds, and you continue the back-and-forth. It runs on the web at claude.ai, in the Claude Desktop app, and on mobile (iOS and Android). There is no setup required.

Unlike Claude Code (which targets software engineering in your terminal) or Cowork (which runs autonomous tasks on your desktop), Chat is the general-purpose surface — perfect for everything from quick questions to in-depth collaborative work.

Quick start: Visit claude.ai, sign in with Google or email, and type your first message. The free plan lets you chat on web, iOS, Android, and desktop with no credit card required.

The chat interface

The interface has three parts: a sidebar that lists your past conversations, a model selector at the top, and the chat area where messages appear. Below is what a typical conversation looks like:

claude.ai/new
+ New chat
Today
Python data analysis
Write a cover letter
Explain quantum computing
Yesterday
Summarize this PDF
Debug my React app
Claude Sonnet 4.6
Explain how Python list comprehensions work, with a simple example.
C

A list comprehension lets you create a new list from an existing one in a single, readable line:

# Without comprehension
squares = []
for n in range(5):
squares.append(n ** 2)
# With comprehension — same result
squares = [n ** 2 for n in range(5)]
# [0, 1, 4, 9, 16]

The format is: [expression for item in iterable]. You can also add a condition: [n**2 for n in range(10) if n % 2 == 0]

Reply to Claude…
📎
↑

Claude Chat — sidebar with conversation history, model selector, and a live Python explanation with inline code

What Claude Chat can do

Claude Chat handles a wide range of tasks out of the box. You can attach files, paste text, or just describe what you need:

✍️
Write & edit
Drafts, emails, essays, scripts, reports — any format or style.
💻
Code
Write, explain, debug, or refactor code in any language.
📄
Summarize
Condense long documents, articles, or meeting notes into key points.
🖼️
Analyse images
Describe, interpret, or extract data from photos and charts.
🌐
Search the web
Get up-to-date answers using real-time web search.
🧠
Think deeply
Extended thinking mode for complex maths, logic, or multi-step reasoning.
🗣️
Translate
Translate between dozens of languages or explain nuances.
💡
Brainstorm
Generate ideas, explore different viewpoints, or act as a debate partner.

How to start a good conversation

Claude works best when you are specific. Compare these two prompts for the same task:

✗ Too vague
Help me with my email.

Claude will have to guess what kind of help you need, who the email is for, and what tone to use.

✓ Specific
Write a short, polite follow-up email to a client who hasn't replied to my project proposal in a week. Keep it under 100 words.

Claude has the format, recipient, context, tone, and length constraint — it will nail it on the first try.

Give context — Tell Claude who you are, what the output is for, and who the audience is.
Set the format — Say "give me a bullet list", "keep it under 200 words", or "respond in JSON".
Iterate freely — Say "make it shorter", "change the tone to formal", or "add a section on X".
Attach files — Upload a PDF, image, CSV, or code file and ask Claude to work with it directly.

Organise conversations with Projects

Projects (available on Pro and above) let you group related conversations under one name. Each project can have a system prompt (instructions that apply to every chat in the project) and uploaded files that Claude references automatically.

📁My Projects
⚖️
Contract Review
Uploaded: contracts/
14 chats
📊
Q2 Data Analysis
Uploaded: sales.csv
8 chats
🎨
Marketing Copy
System: brand voice
22 chats
🐍
Python Tutoring
System: teach gently
31 chats

Example projects — each one has its own uploaded files and system-prompt instructions

Practical example: Create a "Contract Review" project, upload your standard contract templates as files, and set a system prompt like "You are a legal assistant. Always flag missing clauses and identify ambiguous language." — now every chat in that project behaves like a trained specialist.

Choosing a model

You can switch the model at any time using the selector at the top of the chat. Claude currently offers three model tiers:

ModelSpeedPowerBest for
Haiku 4.5Fastest⭐⭐Quick questions, everyday tasks, fast lookups
Sonnet 4.6Balanced⭐⭐⭐⭐Writing, analysis, coding, general-purpose work
Opus 4.7Deliberate⭐⭐⭐⭐⭐Complex analysis, deep research, ambitious projects
Default choice: Sonnet 4.6 is the recommended model for most tasks — it is powerful, fast, and handles coding, writing, and analysis well. Switch to Haiku 4.5 for speed, or Opus 4.7 for the most complex, multi-step work.

When to use Chat, Cowork, or Claude Code

Claude has three main surfaces, each designed for a different kind of work:

You want to…Use ChatUse CoworkUse Claude Code
Ask questions✅ Yes——
Write or analyse✅ Yes✅ Yes (autonomously)✅ With files
Edit local files—✅ Yes — full file access✅ Yes — in repo
Run agentic tasks—✅ Yes — steps automatically✅ Yes — code tasks
Build softwarePair programming (manual)—✅ Primary use case
Works onWeb, mobile, desktopClaude Desktop (Mac/Windows)Terminal / IDE
Claude Chat is the best starting point for almost everything. If you find yourself doing the same multi-step task repeatedly, that is a signal to explore Cowork (for file and app tasks) or Claude Code (for software development).
Key takeaways:
  • Claude Chat is available on the web, desktop, and mobile — free to start at claude.ai.
  • Type naturally, be specific, and iterate — the more context you give, the better Claude responds.
  • Use Projects (Pro+) to group chats with shared files and a system prompt for consistent behaviour.
  • Pick the model that fits the job: Haiku for speed, Sonnet for general work, Opus for deep complexity.
  • When you need Claude to take actions autonomously on your computer, use Cowork or Claude Code instead.

What's Next

Course complete. Claude Chat, Claude Code, Claude Skills, Plugins, and Cowork — you've covered all five tools and how they work together.