What is Claude and why does it matter now?

The right mental model before you start

Claude is not ChatGPT with a different name

Claude is Anthropic's AI model, built by former OpenAI researchers who took a different approach: safety first, capability second. That's not just marketing — it directly shapes how Claude reasons, follows instructions, and behaves under pressure.

Real long context: Claude processes up to 200k tokens without degrading. You can feed it an entire codebase.
Follows complex instructions: multi-step, conditional, specific formats — without making things up.
Honest about uncertainty: it says "I don't know" when it doesn't know. It doesn't hallucinate with confidence.
Built for professional work: code, analysis, technical writing, agents.

What is Claude actually useful for?

Most people use Claude across three broad categories:

Code: review, generation, refactoring, debugging. Claude understands wide project context.
Analysis and writing: documents, reports, emails, proposals. It maintains your tone if you tell it to.
Automation: agents that execute tasks, gather information, orchestrate tools.

TIP

Claude Sonnet 4 is the optimal speed/capability balance for most tasks. Claude Opus 4 when you need deep reasoning. Claude Haiku 4 for simple, high-volume tasks.

The right mental model

Claude is not a search engine or autocomplete. It's a collaborator with reasoning capability. Treat it like a smart colleague you brief well: the more context you give it, the better it works.

The most common mistake: one-line prompts expecting magic. The reality: the best results come from prompts that explain the context, objective, constraints, and expected format.

INFO

In this course you'll learn to use Claude Code — Anthropic's official CLI that integrates Claude directly into your terminal and development workflow.

ejercicio

Your first full-context prompt

Open claude.ai or your terminal with Claude Code. Copy this prompt and observe the difference vs a generic one-liner.

prompt

Act as an expert AI productivity consultant.

Context: I am a [your role] and I primarily work in [your area]. I spend a lot of time on [repetitive task you want to optimize].

Task: Explain in 3 concrete steps how I could use Claude to reduce the time I spend on this task. Include a sample prompt for each step.

Format: Numbered list, maximum 150 words per step, no unnecessary jargon.

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