Claude Code Basics for Non-Programmers

Who this is for: Researchers who have never used a terminal, or who find the terminal intimidating. This document covers installation, first launch, and what the day-to-day experience actually looks like.

What you are installing

Claude Code is a command-line application — a program you run in a terminal (also called: command prompt, shell, console). It is not a graphical app with windows and buttons. You type text, press Enter, read the response.

This sounds more difficult than it is. Within five minutes of first launch, most people forget they are in a terminal.

Two ways to get Claude Code

Option A — No installation (Desktop app): The Claude Desktop app includes a built-in Code tab. Download it from claude.ai/download, sign in, and click the Code tab. No terminal needed. This is the fastest way to start.

Option B — Terminal install: Gives you the full CLI experience with direct control. Requires opening a terminal; no other prerequisites.

The rest of this document covers the terminal install. If you chose Option A, skip to First launch.

Opening a terminal

Mac: Press Cmd+Space, type "Terminal", press Enter. Or: Applications → Utilities → Terminal.

Windows: Press Win+S, search for "PowerShell", press Enter. (Use PowerShell or Windows Terminal — not the old Command Prompt.)

Linux: You know how to do this.

Installation

Mac / Linux / WSL:

curl -fsSL https://claude.ai/install.sh | bash

Windows (PowerShell):

irm https://claude.ai/install.ps1 | iex

This downloads and installs Claude Code. Takes about a minute. Wait for the prompt to return. The installer updates your PATH — close and reopen the terminal before the next step.

The native install auto-updates in the background, so you always have the latest version.

First launch and authentication

Type this and press Enter:

claude

The first time, Claude Code will ask you to authenticate — it will open a browser window for you to log in with your Anthropic account (the same account you use for Claude.ai). Follow the prompts. This only happens once.

After authentication, you will see something like:

Claude Code v1.x.x
Type your message or /help for commands
>

You are in. Type your first message and press Enter.

What the interface looks like

Claude Code looks like a chat — but in a terminal window.

> Summarise this PDF for me: report.pdf

● Reading report.pdf...
● The document is a 2023 annual report from...

  Summary:
  The report covers three main areas...
  [continues]

>

Key things you will notice:

You can scroll back through the conversation. Press Ctrl+C at any time to interrupt Claude if it is doing something you want to stop.

Essential commands

These are the only commands you need to know to start:

Command What it does
/help Show available commands
/clear Clear the conversation and start fresh
/exit Quit Claude Code
Ctrl+C Interrupt Claude mid-task
Ctrl+L Clear the screen (not the conversation)
↑ arrow Recall previous message

That is genuinely all you need for basic use.

Navigating to your files

Claude Code can read any file on your computer by its full path. But it is easier to navigate to the folder you are working in first, so you can refer to files by short names.

To navigate, use the cd command (change directory):

cd Documents/my-research-project

Then launch Claude Code from there:

claude

Now when you say "read report.pdf", Claude Code looks for it in your current folder. You can check where you are with pwd (print working directory).

Tip: On Windows, you can navigate to a folder in File Explorer, then type powershell in the address bar — it opens a terminal already in that folder.

Your first real task

Once you are in the right folder:

> I have a PDF called interview_transcript.pdf.
  Please read it and give me a 3-paragraph summary,
  focusing on what the interviewee says about migration.

Claude Code will read the file from your disk (no upload needed) and respond.

To save the summary to a file:

> Read interview_transcript.pdf and write a 3-paragraph summary
  focused on migration to a new file called summary_interview.md

Claude Code will create summary_interview.md in your current folder.

Working with multiple files

> There are several PDF files in this folder.
  Read each one and tell me which ones discuss the topic of heresy.

Claude Code will find the PDFs, read them, and report back. This is the core capability that Desktop cannot match.

Updating Claude Code

The native install updates automatically in the background. No manual step needed. If you want to force an update immediately, run the same install command again.

Common first-time confusions

"I typed claude and nothing happened / command not found" Node.js or Claude Code may not have installed correctly, or the terminal does not know where to find the program. Try closing and reopening the terminal first. If still broken, reinstall.

"Claude is asking me things / doing things I didn't expect" Press Ctrl+C to stop. Claude Code is an agent — it will take initiative. If it is doing something wrong, interrupt and rephrase your instruction.

"The output disappeared" Scroll up in the terminal window. The conversation is still there.

"I asked Claude to process a file but it says it cannot find it" You are probably in the wrong folder. Use pwd to see where you are, cd to navigate to the right place, then try again.

"This feels slower than Desktop" Claude Code thinks before it acts — it plans tool use, executes, observes, continues. This is visible in the terminal. For simple questions it is the same speed. For tasks involving files, the extra time is Claude actually doing the work.

Further learning: Claude Code in Action — Anthropic Academy — free video course from Anthropic with hands-on walkthroughs of real workflows. Official documentation — full command reference and configuration guide.

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