ChatGPT uses trained AI models to generate a response from your request and the context available in the conversation.
For text, the model processes small chunks called tokens. Its training helps it recognise patterns in language and produce a useful continuation. Your instructions, earlier messages and any material you supply help shape the result. That is why asking for a short explanation for a beginner can produce a different answer from asking for a technical report.
The model is one part of the product. Depending on the tools available, ChatGPT can also search the web, analyse a file or run code. A reply based on a web search has a different source of information from a reply generated without one. Ask it to show the sources when the answer depends on current facts.
Try this: paste a short, non-sensitive email and ask for a warmer version under 100 words. Then ask it to explain the changes. You can steer the same conversation instead of starting again. Check names, dates and factual claims before sending the result; a fluent sentence can still contain a very confident mistake.
ChatGPT is OpenAI's AI assistant; OpenAI is the company behind the product and the models used to power it.
It helps to separate the app from the model. ChatGPT is the service you use through its website and official apps. A GPT model is the underlying technology that can also be made available to developers through an API. Another app using an OpenAI model does not automatically become ChatGPT.
That distinction matters when you pay. A subscription sold by a third-party chatbot belongs to that service, with its own limits, billing and data terms. It does not necessarily give you a paid ChatGPT account. Before subscribing, check the developer or seller and the website handling the payment.
For example, if a writing app advertises access to GPT models, ask whether you are buying that app's features or an OpenAI subscription. Both can be useful, but the receipt should tell you which one you bought. The model name on the box does not settle the question.
ChatGPT has a free plan and paid subscriptions; Plus is listed at US$20 per month, while API usage is billed separately.
That is the published US-dollar reference price checked on 24 October 2026. Your checkout can differ because of local currency, applicable taxes or the store handling the purchase. Other individual and organisation plans are available, so Plus is one option rather than the price of every ChatGPT account.
Choose a plan around a task you actually repeat. Occasional explanations and short drafts may fit the free option. If a limit regularly interrupts your work, compare the paid plan's current allowances with what you need. A more expensive subscription is not a guarantee that every answer will be correct.
Building an app is a different budget. API requests have their own usage charges, and a Plus subscription does not act as an API wallet. Keep the two lines separate when you estimate costs: the subscription for your own work, and the API bill for software making requests. Start with the free plan if you are still finding out whether the tool earns a place in your routine.
ChatGPT Plus is OpenAI's paid individual subscription, listed at US$20 per month, with additional access and usage allowances compared with the free plan.
Think of it as a subscription to the ChatGPT product. The particular models, tools and allowances can change, and availability can depend on your account or region. Check the current plan page and your account's limits instead of treating an old screenshot as a permanent feature list.
Plus does not mean unlimited use of every feature. Longer tasks, files and tools can use more of an allowance than a short question. It also does not include a prepaid OpenAI API balance; using the API in your own application has separate billing.
A sensible reason to upgrade is specific: you use the product regularly and a free-plan limit repeatedly stops a useful task. If you only need a few short answers each week, try that workload before paying. Paying for a bigger allowance can remove a bottleneck, but it cannot decide whether the finished work is any good.
It depends on the data, your account and the controls in place; check those before uploading anything confidential to ChatGPT.
Separate the products first. OpenAI states that business data is not used for training by default, and API data is not used for training unless you opt in. Those statements do not mean every personal account, connected tool or third-party chatbot has identical terms. A paid personal subscription should not be treated as proof that your employer has approved the service.
Training and storage are also different questions. For example, the API can retain abuse-monitoring logs even when data is not used for training. Before sharing a document, review the controls for your account, who can access or receive the information, and any rules set by your organisation.
For a practical first step, replace customer names, account numbers and other unnecessary details with placeholders. Ask for help with a sample or a short extract rather than uploading the whole folder. If the job requires confidential company material, use the approved workspace and process. A chatbot can help tidy a spreadsheet without needing everybody's passport number.
Claude is Anthropic's AI assistant, which you can use for tasks such as explaining information, writing, analysing material and working with code.
You can talk to Claude through its web, desktop and mobile apps where the service is supported. Anthropic also provides developer access to Claude models. As with other AI products, the model, tools and limits you can use depend on how you access it and the plan available to your account.
A useful starting task is to give it a non-sensitive document and ask for the main points, unanswered questions and a short action list. Explain who the summary is for. A handover note for a colleague needs a different level of detail from an introduction for somebody new to the topic.
Claude can also help draft and revise text or explain a piece of code. Review the result against the original material, especially names, figures and quotations. If you are comparing it with ChatGPT or Gemini, give each the same small task and judge the finished output. You do not need to subscribe to all three to begin that comparison.
Gemini is Google's AI assistant and the name of its AI model family, with capabilities that can handle text, images, audio and other kinds of information.
The name appears in several places. The Gemini app is the assistant you talk to directly. Gemini models can also power features inside other products or be used by developers. Access in one place does not automatically give you every feature or allowance in another.
For a simple test, upload a non-sensitive document and ask for a short summary plus a list of details worth checking. Or ask it to explain a concept using an example from your work. Available file handling, connected apps and generation tools depend on the version and access you have.
Google's own overview explains that Gemini can produce inaccurate or invented information. Open cited sources, compare important figures with the original document and do not assume a response is verified just because it comes from a Google product. If you are considering a paid plan, check which part of your actual workflow it improves before comparing subscription names.
Microsoft Copilot is Microsoft's AI assistant, with features for answering questions, creating content and helping with work in Microsoft apps.
The account you use matters. A personal account and a work or school account can have different access, features and data controls. Microsoft says its Copilot app adapts to the account and subscription, so check what your own licence includes rather than assuming every screenshot describes your version.
One practical use is preparing a draft document or presentation from material you are allowed to share. In a work environment, some capabilities can use organisational content, depending on your licence and access. Before asking it to summarise a meeting or a company file, check that the relevant feature is available in your workspace.
Also check the full product name when comparing prices. Microsoft Copilot and GitHub Copilot are different products, even though they share the Copilot name. GitHub's product focuses on software development. If your goal is help in Word, Excel or PowerPoint, compare the Microsoft account and app features you will actually use. The family resemblance does not make the subscriptions interchangeable.
Perplexity is an AI search and answer service that combines generated explanations with links to sources you can open and check.
Instead of only giving you a list of pages, it can search for information and put together an answer. Its Pro Search feature can break a more complex question into searches and combine information from several sources. The tools and allowances available depend on your access and plan.
Try a question with a clear comparison: ask for the differences between two software plans, with links to the providers' own pricing pages. Then open those pages yourself. Check the date, currency and billing period, and make sure the cited page actually supports the sentence next to it.
Sources make checking easier; they do not make every summary correct. A citation can point to old information or support only part of a claim. Perplexity is useful for finding a starting set of sources and exploring follow-up questions, while the original material remains the place to confirm a detail before you spend money or repeat it as fact.
Grok is an AI assistant for conversation, writing, research and other tasks, available through grok.com and its mobile apps.
Its features include working with uploaded files, generating images and using search. The official consumer FAQ describes searches of the web and public posts on X. For current events, check whether search was used and follow the sources rather than assuming the model's stored knowledge is up to date.
For example, ask it to find the original announcement behind a technology story, then compare that announcement with the summary. Social posts can help you find a discussion quickly, but a popular post and a reliable source are not the same thing.
Grok is free to start, with paid plans offering additional access and higher limits. Check the route you are buying through: the standalone Grok service, access through X and developer API usage can have different terms. Compare the allowance for the feature you need, such as file analysis or image generation, before choosing a plan.