The basics

AI

Short for Artificial Intelligence. A computer program that can think and respond the way a person would. It can write, answer questions, summarise documents, and a lot more. ChatGPT, Claude, and Gemini are all AI tools.

LLM

Short for Large Language Model. The technology that powers AI assistants like Claude, ChatGPT, and Gemini. You don’t use an LLM directly. You use the product built on top of it. GPT-5 is the LLM. ChatGPT is the product. Gemini 3 is the LLM. The Gemini app is the product.

AI Assistant

A tool you talk to by typing. You type what you need and it types back. Claude, ChatGPT, and Gemini are all AI assistants.

AI Prompt

The message you type to an AI. Think of it like giving someone a task. The more specific you are, the better the result. “Write a friendly reply to a customer asking about my refund policy in my tone of voice (see attached)” gets a much better answer than “write an email.”

AI Response

What the AI sends back after you type your prompt.

AI Conversation

The back and forth between you and the AI. You type, it replies, you type again. It all stays in one thread. You can keep going as long as you need to. When you start a new chat, it’s a fresh start.

Tool Model

The engine running behind the tool. Claude uses Opus and Sonnet. ChatGPT uses GPT-5. Gemini uses Gemini 3. You don’t need to think about this much. A paid plan gives you access to the best one available.

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How AI reads and remembers

Tokens

These are a small chunk of text, roughly one word or part of a word. AI tools measure everything in tokens. Your message, the reply, any files you upload. The longer your message or document, the more tokens it uses. This is why heavy users hit limits faster. You don’t count them yourself, it happens in the background.

Context windows

How much text the AI can hold in memory at one time. Your messages, its replies, anything you have uploaded. Think of it like a whiteboard. Once it fills up, older content gets pushed off. For most everyday business tasks you will never come close to filling it.

Input

Everything you send to the AI. Your message, a document, an image, a spreadsheet.

Output

Everything the AI sends back. A written reply, a document it created, an image it generated.

Memory

The ability to remember things about you across different conversations. You tell it once that you run a yoga studio in Cape Town and it can use that context every time you come back, without you having to explain again. Available on paid plans for all three tools.

Session

A session used to mean one conversation. That is still true for basic chat. But in 2026 a session can also mean an AI agent working through a task on your behalf, without you typing anything. It reads files, makes decisions, takes steps, and finishes the job. A session ends when the task is done or you stop it. Memory can carry information from one session to the next.

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Features and tools

Project (Claude)

A workspace inside Claude where your documents and instructions are saved and remembered across every conversation. You set it up once with your business information, your tone, your common tasks, and Claude uses it every time you open that project. A photographer could load in her pricing, her contract terms, and how she likes to communicate with clients. Every conversation in that project has that context already loaded.

Project (ChatGPT)

ChatGPT has Projects too. A space where your files and instructions are saved and available every time you open it. A Project is your personal workspace. A Custom GPT is different, it is a tool you set up to do one specific job.

Custom GPT

A version of ChatGPT you set up to do one specific job, every time you open it. You give it instructions once and it follows them every time. A florist could build one that always writes in her brand voice and knows her seasonal products. She opens it, types the task, done. Available on Plus and above.

Gem

Gemini’s version of a custom workspace. Same idea as a Custom GPT. You give it a purpose and instructions and it behaves that way every time.

Web search

The ability for an AI to search the internet for current information. Useful when you need recent news, current prices, or anything that changes over time. All three tools have it.

File upload

You can upload a document, spreadsheet, PDF, or image and ask the AI to read it, summarise it, or answer questions about it. Useful if you want to paste in a supplier contract and ask it to flag anything unusual, for example.

Image generation

The ability to create an image from a text description. You describe what you want and it makes it. ChatGPT and Gemini can do this. Claude cannot. Useful for social media graphics, flyers, product mockups.

Voice mode

Talking to the AI instead of typing. It speaks back. Useful if you are on the go, working with your hands, or just find it easier than typing. Available in ChatGPT and Gemini on paid plans.

Deep Research

A feature that automatically searches hundreds of websites and pulls together a detailed report on any topic. Gemini and ChatGPT both have it. Useful if you need to research a supplier, understand a market, or prepare for a meeting. It does the legwork, you review the findings.

File creation

The ability to create a real downloadable file. A Word document, a spreadsheet, a PDF, a presentation. Claude is the strongest for this. ChatGPT and Gemini can do it too but with more limitations.

Connectors

Links between an AI tool and other apps you already use. Google Drive, Gmail, Shopify, Slack. When these are connected, the AI can read from those apps and sometimes act inside them. A shop owner with Shopify connected could ask Claude to pull her recent orders without copy-pasting anything. Available on paid plans.

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Limits and usage

Usage limit

A cap on how many messages you can send in a set time period. All three tools have limits on free and entry-level paid plans. When you hit the limit you wait for it to reset or upgrade your plan.

Rate limit

Similar to a usage limit. A restriction on how fast you can send messages. If you send too many in a short time the tool slows down or pauses briefly.

Message cap

The maximum number of messages before you hit your limit. On the ChatGPT free plan it is roughly 10 messages every 5 hours. Paid plans are much higher.

AI credits

A separate allowance for specific features, mainly image and video creation. Gemini uses credits for these. Regular text conversations do not use them. The free plan gives you a set number each month.

Free tier

The no-cost version of each tool. Good for trying things out. Comes with message limits and fewer features. On ChatGPT and Gemini free plans, you will also see ads.

Paid plan

A subscription that gives you more messages, better models, and more features. All three tools start at around $20 per month for their main paid plan. Claude Pro and ChatGPT Plus are both $20 per month. Gemini AI Pro is $19.99 per month. This is where the real value kicks in for business use.

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Privacy and data

Training data

Information AI companies use to teach their models. On free plans your conversations may be used to help improve the AI. On most paid plans this is turned off by default.

Data retention

How long the AI company keeps your conversations. This varies by tool and plan. If you are sharing sensitive client information, it is worth checking the privacy settings on whichever tool you use.

Incognito / temporary chat

A mode where your conversation is not saved and not used for training. Available on ChatGPT and Claude. Useful if you are working with sensitive information.

System prompt

A set of hidden instructions that controls how an AI behaves. Businesses that build tools on top of AI use these to set rules. A tool built for a legal firm might have a system prompt telling it to always recommend consulting a lawyer. As a regular user you will not see these unless you are building your own custom tool.

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Things people often confuse

AI Agent

An AI that does tasks on its own, not just answers questions. You give it a goal and it works through the steps to get there. It can read files, search the web, send emails, and make decisions along the way without you approving each step. Claude’s Cowork feature is an example. So is ChatGPT’s Agent Mode. Different from a chatbot, which just responds to what you type.

AI vs automation

AI responds to what you ask it. Automation runs set steps without any thinking involved. A tool that automatically sends a booking reminder at a set time is automation. Claude writing a reply to a client email is AI. They can work together but they are different things.

Hallucination

When an AI confidently gives you information that is wrong or made up. All three tools do this occasionally. Claude tends to flag when it is not sure rather than guessing. Always check anything important, especially facts, figures, or legal information.

ChatGPT vs GPT

GPT is the underlying model, like an engine. ChatGPT is the product built on top of it, like the car. When people say ChatGPT they usually mean the product at chatgpt.com.

Claude vs Anthropic

Anthropic is the company. Claude is their AI assistant, the product you use at claude.ai.

Gemini vs Google AI

Google has several AI tools. Gemini is the one built for everyday use. When you see Gemini appearing inside Gmail or Google Docs, that is the same thing.

Prompt engineering

Writing better prompts to get better results from AI. It sounds technical but it just means being clear and specific. “Write a short friendly reply to a client who missed their appointment, keep it warm and do not make them feel bad” is prompt engineering. You are already doing it when you think about how to phrase a message well.

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Covers Claude, ChatGPT, and Gemini. Prepared by Content Station. Last reviewed May 2026.