What Claude is (and why it's different)

TL;DR

Claude is an AI from Anthropic that converses, reads files, reasons about them, and runs tools. It’s not a chatbot. It’s a coworker that understands long context.

Captura de tela

Claude.ai home screen, logged in

claude.ai

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Side menu

2

Chat box

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Model + tools

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Avatar

Abrir ↗

1. 1 Side menu — projects, saved chats, settings
2. 2 Chat box — paste text, attach a file, ask
3. 3 Model + tools — switch between Opus/Sonnet/Haiku, enable connectors
4. 4 Avatar — plan, settings, skills

Why Claude, and not another AI

Three things make Claude practical for business:

1. 1 million token context. It means it reads your 200,000-row spreadsheet, your entire P&L, and still remembers the start of the conversation when it gets to the end.
2. Deep reasoning (Adaptive Thinking). Before answering, it thinks in steps. For an important problem, it justifies itself.
3. Real actions. It doesn’t just chat. It runs code, reads Drive files, sends email, builds spreadsheets — when you tell it to.

The three models in the family

Model	When to use	Relative cost
Opus 4.7	Complex tasks, important decisions, critical analysis	Most expensive
Sonnet 4.6	Daily work, balance of quality and cost	Medium
Haiku 4.5	Repetitive tasks, high volume, fast responses	Cheapest

For a founder starting out: use Sonnet 4.6. It’s the default in Claude.ai and covers 90% of needs.

Where you use Claude (surfaces)

The same AI shows up in several places. Each one serves a different moment:

• claude.ai — Web. This is where you start. Load a spreadsheet, chat, get a report.
• Claude Desktop (macOS and Windows) — Native app with local file integration (Cowork).
• Claude on Chrome — Extension. Ask Claude about any open page.
• Claude on Slack / Microsoft 365 — Bot that lives in your team’s conversation.
• Claude Mobile — iOS and Android. Useful for triaging email on the go.
• Claude Code — For programmers. Edits code, automates repos.
• API (platform.claude.com) — To integrate Claude into your own system.

What it can do (and what it still can’t)

Can do

• Read a spreadsheet (Excel, Google Sheets, CSV) and analyze it like a senior analyst.
• Read a PDF, contract, email, internal policy.
• Generate text, copy, email, report, deck.
• Run Python code on the spot to perform statistical analysis.
• Connect with Drive, Gmail, HubSpot, Notion, Calendar (via connectors).
• Search the web (with Web Search enabled).
• Remember what you discussed in previous sessions (in Projects).

Still can’t (well)

• Operate voice agents on real phone calls.
• Make decisions without you confirming (on irreversible actions).
• Read poor handwritten images without losing information.
• Replace human judgment in high-ambiguity situations.

Step-by-step — creating your first account

1. Go to claude.ai
2. Click Sign up (or Sign in with Google)
3. Confirm your email
4. Recommended: subscribe to Claude Pro ($20/month) to unlock 1M context, connectors, Skills, and heavy use. The free plan limits use per hour.
5. In Settings → Profile, write 2-3 sentences about you and your business. Claude uses this to personalize answers.

Common gotchas

• Don’t dump your entire business life into a single prompt. Use Projects (Claude.ai > Projects) to separate contexts: “Sales”, “Finance”, “Strategy”.
• Confidential? Claude Pro doesn’t train AI on your data. But for highly sensitive information, consider Claude Enterprise or ZDR (Zero Data Retention).
• Don’t trust numbers it makes up. When Claude has Analysis code enabled, ask it to execute the calculation. Without that, numbers can be estimates.
• Language: it speaks perfect English. But some complex prompts work better in English because the training base is larger. Try both when the result comes out weak.

Next step

Now that you know what Claude is, learn how to talk to it in a way that extracts the maximum — prompt engineering for founders.