You have probably heard of Claude, and maybe you use it now and then. But what actually happens when you type a question and an answer comes back? This article explains in plain language how Claude works, which model to pick when, and what you do with it in your daily work. If you first want to know what Claude is and where it comes from, read what is Claude. Here it is all about how it works.
How does Claude work under the hood?
Claude is trained on huge amounts of text and, based on that, predicts the best continuation of what you type. Put simply: it has seen so much language that it recognises patterns and builds a logical, fitting answer word by word. That sounds like guessing, but in practice you get a coherent answer that takes your whole question into account.
Something important to grasp: Claude does not "know" the way a database knows a fact. It works out what the most likely, useful continuation of your text is. That is why the way you ask something shapes what you get back. Give it context, an example and a clear instruction, and the answer gets better.
The newest Claude models can also reason step by step before they answer. Instead of blurting out the first thing that comes up, they work a problem through internally first. You notice this on harder tasks: a calculation, a legal judgement or a piece of code comes out more considered than with simple autocomplete.
What makes Claude stand out is how much it can take in at once. The newest models process up to a million tokens in one go (mid-2026), roughly a stack of five thick books. So you can drop a whole contract, annual report or manual into it and ask questions without Claude losing the thread.
The Claude models: which one do you pick when?
Claude is not one model but a family. Anthropic offers three lines, each with a different balance between speed, cost and power. You pick not on brand name but on what the task needs.
| Model | What it stands for | When you pick it |
|---|---|---|
| Claude Haiku | Fast and cheap | Short, simple tasks: summarising, classifying, quick answers |
| Claude Sonnet | The all-rounder | Most daily tasks: writing copy, analysing documents, thinking along |
| Claude Opus | The most powerful | Complex analysis, hard problems, code and work where top quality matters |
In practice most people do fine with Sonnet as their default. Reach for Haiku when something mainly needs to be fast and simple, and switch to Opus when a question really requires deep thinking and quality counts. If you use Claude through the app, you pick the model in a menu; there is nothing technical to set up.
What you actually do with Claude
Claude's value is not in a list of features but in what it solves in your own work. A few examples per profession.
Business owner. Have Claude draft a quote from a few bullet points, summarise a long email thread into a decision, or think along about the price of a new service. Paste in your meeting notes and ask for an action list with owners and deadlines.
Marketing. Write a first draft of a blog, rewrite a text in a different tone, or come up with ten variations of an ad headline. Feed in your brand guidelines and Claude sticks to your style. Ask for a content calendar based on your themes.
Finance. Upload a set of accounts or a batch of invoices and ask Claude to pull out anomalies, trends or the key items. Have it explain a complicated tax rule in plain language, or work through a budget scenario you describe in words.
Legal. Put a contract next to your standard terms and ask which clauses differ. Have a long agreement summarised into the points that actually matter, or ask what risks sit in a liability clause. The result is a starting point for your own assessment, not legal advice.
Claude takes the first-draft thinking and the tedious analysis off your plate; you keep the control and the judgement.
How to get started with Claude
You do not need technical knowledge to start. You are on your way in a few steps.
1. Create an account at claude.ai. There is a free version with limits so you can try it. If you want more usage and access to all models, Claude Pro is 20 dollars a month. For teams and companies there are Team and Enterprise plans. 2. Choose where you work. Claude runs in your browser, as a desktop app on your computer, and on your phone. Your conversations carry across those devices. 3. Type your first instruction. Do not start with a vague "help me with marketing", but with context and a concrete question: "I run a painting business with five staff. Write a short quote text for a client who wants their window frames painted." The more context, the better the answer. 4. Upload a document. Drag a PDF, Word file or spreadsheet into the conversation and ask questions about it. This is where Claude really saves time: let it read the long pieces you no longer have to wade through yourself. 5. Keep talking. If you do not get what you want straight away, just correct it: "shorter", "more formal", "drop the jargon". Claude remembers the conversation and builds on it.
The biggest leap comes not from one perfect prompt but from steering the conversation until the output is right.
What Claude cannot do
Being honest about the limits is part of it, because that decides how you use it safely.
Claude can make up facts. Because it predicts the most likely continuation, a wrong answer sometimes sounds just as convincing as a right one. This is called hallucinating. Always check names, figures, quotes and legal details yourself before you rely on them.
Claude has a knowledge cut-off. It is trained up to a certain point and does not know events after that, unless you supply the information yourself or use a version that can look things up on the web. If you ask about something from last week, give it the source.
Claude does not make decisions for you. It gives a reasoned proposal, but the judgement about an investment, an assumption or a contract stays yours. Use the output as a starting point, not an end point, on important choices.
And Claude does not know your company by default. It knows nothing about your customers, prices or internal agreements unless you feed them in. If you want an AI that structurally knows your business and runs along in your processes, that is a separate step, for example an agent on your own infrastructure.
Claude vs ChatGPT in short
Both are strong language models and for many tasks you barely notice a difference. Claude is known for handling long documents, nuanced answers and the quality of its reasoning. ChatGPT has a broader ecosystem and more features around image and audio. The best choice depends on what you need, and many people use both side by side. Want the other side of the comparison, read what is ChatGPT.
The Claude ecosystem: Code, Cowork and OpenClaw
Claude in your browser is the start. Around it sit tools that put the model to work in a different way.
Claude Code is the version for developers, working directly in the terminal and your codebase instead of a chat window. More in what is Claude Code.
Claude Cowork brings Claude to non-technical tasks as a digital colleague, with connections to Office programs among others. Read on in what is Claude Cowork.
OpenClaw is an open-source agent framework that can use Claude, among other models, to carry out tasks on its own. That is how you put Claude to work as the engine of an agent that does real work. More at OpenClaw.
One more point that matters for businesses: Anthropic does not use business customer data for training by default, which is stated in their terms. For anyone working with sensitive data, that is a meaningful difference from some free tools.
Frequently asked questions
How does Claude work in short? Claude is trained on huge amounts of text and, based on that, predicts the best continuation of what you type, step by step. You ask a question or give a task, Claude reads it, reasons about it and writes an answer. It can read and analyse long documents, and the newest models process up to a million tokens in one go.
Is Claude free to use? Yes, there is a free version with limits at claude.ai. If you want more usage and all models, Claude Pro is 20 dollars a month. For teams and companies there are Team and Enterprise plans. You use Claude through the browser, a desktop app and your phone.
Which Claude model should I choose? For most tasks Claude Sonnet is the logical default. Pick Claude Haiku when something mainly needs to be fast and simple, and Claude Opus when a question really requires deep thinking and quality counts heavily. In the app you pick the model from a menu.
Can Claude make mistakes? Yes. Claude can make up facts that sound convincing but are wrong, which is called hallucinating. It also has a knowledge cut-off and knows nothing about your company unless you feed it in. Always check names, figures and legal details yourself on important decisions.
Does Anthropic use my data to train Claude? Anthropic does not use business customer data for training by default, which is stated in their terms. Anthropic is an AI company with a strong focus on safety. If you work with sensitive data, always check the terms of the plan you are using.
What is the difference between Claude and an AI agent? Claude is the language model: you ask a question and get an answer. An AI agent uses such a model as an engine to carry out tasks and run processes on its own. Claude does not know your business by default; an agent is set up precisely to know your business and run along with it.
Learn faster than figuring it out yourself
You can discover Claude entirely on your own. But most business owners lose weeks doing so, trying things and giving up at the first disappointing output. It goes faster when someone who works with it daily sits next to you and translates it to your work.
In 1-on-1 AI training you learn in 3 hours over Teams exactly how to use Claude for your tasks, with your own examples on the table. The training is a one-off 349, 449 or 579 euros excluding VAT, depending on the level. Your trainer is Tarik Eraslan, AI implementation coach and AI trainer.
If you want to get better not once but continuously as AI changes every month, look at AI coaching: 399 euros a month excluding VAT, with the first month as a trial month. You stay steered each month and keep your knowledge current.
Not sure yet what fits your situation? Book a no-obligation call and we will honestly discuss what helps you most.
