ChatGPT: what it is, how it works, what it can do, how to use it and what its limitations are

ChatGPT is a generative artificial intelligence assistant developed by OpenAI that lets users interact with an AI system through natural language. It can answer questions, explain concepts, write and rewrite texts, translate, analyse files and images, assist with programming, search the web and support personal and professional tasks.

Launched as a conversational chatbot in 2022, ChatGPT has progressively evolved into a far broader platform. Its features now include conversation, search, data analysis, image generation and editing, voice, document upload and, depending on the plan and tools available, specialised modes for more complex research and work tasks.

This evolution makes it necessary to distinguish ChatGPT from the model that powers it. ChatGPT is the interface and ecosystem through which the user works with artificial intelligence; GPT models, by contrast, are the AI systems that process requests and generate responses.

What is ChatGPT?

ChatGPT is a conversational AI assistant designed to understand instructions given in natural language and to produce answers consistent with the context of the conversation.

The name stands for Chat Generative Pre-trained Transformer and refers to the generative language model technology underpinning the system.

What made ChatGPT so widespread is the ability to interact with artificial intelligence much as one would in a conversation. Users do not need to know a programming language or use technical commands: they can describe what they want to achieve and then correct, expand on or modify the request.

The second request provides more information about the context, the objective, the audience and the expected result. This allows ChatGPT to produce output that is generally closer to the user’s needs.

OpenAI describes ChatGPT as an AI assistant for everyday and professional tasks, including brainstorming, writing, studying, planning, maths, programming and the analysis of images and files.

ChatGPT and generative artificial intelligence: what is the difference?

ChatGPT is an application based on generative artificial intelligence, but the two concepts are not synonymous.

Artificial intelligence is a very broad field encompassing systems designed to perform tasks normally associated with human intelligence. Generative AI, by contrast, is a category of systems capable of creating new content from the inputs they receive.

Depending on the technology used, a generative AI system can produce:

• text;
• images;
• audio;
• video;
• code;
• summaries and transformations of existing content.

ChatGPT uses this generative capability within a conversational interface. The user provides an instruction, ChatGPT processes the available context and returns a result.

It is therefore more accurate to describe ChatGPT as a generative, conversational AI service based on models from the GPT family, rather than simply treating it as a synonym for artificial intelligence.

How does ChatGPT work?

ChatGPT is built on artificial intelligence models trained to recognise relationships and patterns in the data used during the training process.

Put simply, when a prompt is sent, the system analyses the information in the request and the available context, then generates a response through the model selected or used for that specific task.

How it actually works is far more complex than simply retrieving a ready-made answer from a database.

A language model does not necessarily “look up” a sentence that has already been written and copy it. It generates output based on the relationships learned during training and on the information available at the time it responds.

This also explains one of ChatGPT’s most important characteristics: an answer can be phrased in an extremely natural and convincing way even when it contains an error.

AI should therefore not be regarded as an automatically infallible source.

The role of the language model

Large language models, commonly referred to as LLMs, are designed to process language and generate content based on the instructions they receive.

ChatGPT uses GPT models that are updated over time. For this reason, talking generically about “how ChatGPT works” without considering the model in use can be reductive: capabilities, tools, limits and ways of using it may change as the platform evolves.

OpenAI offers different models and levels of access depending on the plan and the feature being used.

OpenAI: who created ChatGPT?

ChatGPT is developed by OpenAI, an artificial intelligence research and development company founded in 2015. OpenAI was initially set up as a non-profit organisation with the stated aim of developing artificial general intelligence in a way that would benefit all of humanity. Those involved in its founding included Sam Altman, Elon Musk, Greg Brockman, Ilya Sutskever and other researchers and entrepreneurs from the technology sector.

In 2019 OpenAI created a for-profit subsidiary to raise the capital needed to cover ever-higher research and infrastructure costs. The structure was updated again in 2025: today the non-profit OpenAI Foundation controls OpenAI Group PBC, a public benefit corporation that runs the commercial activities. 

ChatGPT arrived long after the company was founded. OpenAI unveiled it publicly on 30 November 2022 as a research preview based on a conversational model capable of answering follow-up questions, acknowledging certain mistakes and following instructions given in natural language. Since then, ChatGPT has become one of the company’s flagship products, but OpenAI and ChatGPT are not synonymous. OpenAI develops models, infrastructure and other artificial intelligence products; ChatGPT, by contrast, is the assistant through which users can access some of these technologies.

Is ChatGPT a search engine?

No, ChatGPT and a search engine are not the same thing.

A traditional search engine is designed primarily to find and rank web pages and other resources available online.

ChatGPT, by contrast, is a conversational system designed to understand requests and produce responses.

The distinction, however, has become less clear-cut than in the early versions of the service. ChatGPT can in fact use web search tools to retrieve up-to-date information when this feature is available.

This means that ChatGPT can now be used both for a question based on the model’s own knowledge and for a search that requires information available online.

The distinction remains important because an answer generated by the model should not automatically be interpreted as the result of a real-time web search. When up-to-date information is essential, it is advisable to use the available search features and check the sources.

OpenAI lists web search among the tools that can extend ChatGPT’s capabilities.

What can ChatGPT do?

The ways ChatGPT can be used are very broad and depend on the model, the plan and the tools available.

The main applications cover writing, research, analysis, study, programming, creativity, productivity and information management.

Writing text

ChatGPT can create a first draft from just a few instructions or work on an existing text.

It can be used for articles, emails, press releases, product descriptions, social media posts, presentations, letters, documentation, advertising copy, scripts and editorial content.

Of course, the greatest value does not necessarily lie in asking the AI to “write everything”, but in using it as a support tool during the creative process.

It can, for example, help develop a structure, suggest alternatives, identify repetitions, improve clarity or adapt the same message to different audiences.

Rewriting and correcting content

ChatGPT can work on an existing text while, when requested, preserving its original meaning.

You can ask it to correct grammatical errors, improve readability, make the text more professional, simplify technical language, change the tone, reduce the length, expand a passage, remove repetition or adapt the content to a particular audience.

This function is particularly useful when the goal is not to generate content from scratch, but to improve existing content.

Summarising information

ChatGPT can summarise texts and documents, identifying the main concepts, key points and relevant information.

For example, it can turn a long document into a summary, a bullet list, an executive summary, an outline, a comparison table or questions and answers for study.

When working with important documents, however, it is always advisable to check that the summary has not removed a condition, a clarification or a necessary piece of information.

Translating

ChatGPT can translate content between different languages and, beyond literal translation, can adapt register, tone and terminology.

It can be useful, for example, for translating emails, documentation, web pages, marketing content, product descriptions and professional communications.

For particularly sensitive legal, medical, technical or contractual texts, machine translation should still be reviewed by a professional.

Explaining complex concepts

One of the strengths of a conversational assistant is the ability to adjust the level of depth progressively.

You can ask:

“Explain machine learning to me.”

and then continue with:

“Explain it to me as if I had no technical knowledge.”

or:

“Now explain the difference between machine learning and deep learning with a business example.”

The conversation therefore allows the explanation to be built up progressively, rather than necessarily receiving the same answer as every other user.

Supporting study

ChatGPT can be used as a study aid to explain topics, create summaries, build outlines, generate questions, simulate oral tests, practise problems, compare concepts and identify unclear points.

The most effective use is not to hand over studying entirely, but to turn ChatGPT into an interactive tool for checking understanding.

Writing and analysing code

ChatGPT can support developers and technical users in writing and analysing code.

It can help to generate functions, explain existing code, identify possible errors, suggest changes, convert code from one language to another, create queries, work with regular expressions and reason about the structure of an application.

For real development work, however, AI-generated code must be reviewed, tested and subjected to standard security checks.

Analysing data

Data analysis features, where available, make it possible to work with structured files such as spreadsheets and CSVs.

ChatGPT can be used to explore datasets, identify trends, calculate statistics, clean data, create visualisations, compare values and interpret results.

OpenAI explicitly lists data analysis among the platform’s available features.

Analysing images and files

ChatGPT can analyse images, screenshots, charts, documents and other supported files.

You can, for example, upload an image and ask for a description, or provide a document and ask for its main concepts to be extracted.

This considerably broadens the idea of a chatbot: interaction no longer has to be based on text alone.

OpenAI lists file and image uploads among ChatGPT’s features.

Generating images

ChatGPT can also be used to create images from natural-language descriptions and, where the features support it, to edit existing images.

Users can describe the subject, setting, style, composition and visual characteristics, leaving the system to turn the request into an image.

This capability also makes AI useful in creative and visual communication work.

Conversing by voice

ChatGPT also offers voice modes that allow you to interact by speaking rather than typing.

The availability of voice features may depend on the device, the plan and the mode being used.

How do you use ChatGPT?

To start using ChatGPT, simply open the service, type a request into the conversation box and send it. ChatGPT is available on the web and through mobile apps for iOS and Android. In some supported regions it can also be tried without creating an account.

The request you send is commonly called a prompt.

A prompt can be very simple or extremely detailed.

How to write a good prompt

There is no single formula for writing a good prompt, but an effective request tends to specify at least:

1. what needs to be done;
2. for what purpose;
3. for which audience;
4. in what tone or format;
5. any constraints.

For example:

“Analyse this text from an SEO perspective. The audience is Italian business owners. Identify the main content gaps and return a table showing the issue, priority and proposed action.”

is generally more useful than:

“Analyse this text.”

The quality of a prompt, however, does not depend on its length. A very long but confused prompt can be less effective than a short, precise request.

The advantage of conversation

One of the most important features of ChatGPT is that you do not need to phrase everything perfectly in your first request.

You can continue the conversation:

“Shorten the answer.”

“Keep the meaning but use a more professional tone.”

“Add an example.”

“Now turn it into a table.”

“Take this new data point into account as well.”

The conversation therefore allows the result to be refined step by step, rather than treating each request as an entirely separate operation.

Is ChatGPT free?

Yes, ChatGPT has a free plan, but access to features and usage limits depend on the plan and may change over time.

The Free plan includes a range of features, among them chat, web search, data analysis, image and file uploads, use of GPTs and image generation, within the limits set by the plan.

There are also paid plans that may offer higher limits and additional models and tools.

This is why the question “Is ChatGPT free?” should be kept separate from “Are all ChatGPT features free?”. The two are not the same.

Free access lets you use the service, but some features, models or usage levels may be reserved for paid plans or subject to different limits.

What are ChatGPT’s plans?

ChatGPT’s offering comprises different tiers designed for different needs, from occasional personal use through to professional and organisational settings.

Features may change over time, but the general distinction concerns:

• usage level;
• available models;
• message limits;
• advanced tools;
• research capability;
• features for work;
• workspace management;
• tools for teams and organisations.

For users who rely on ChatGPT heavily for professional work there are plans such as Plus and Pro, while Business and Enterprise are designed for organisational settings.

OpenAI also specifies that the availability of certain models and features varies by plan.

For this reason, it is best always to check the official plans page before comparing prices and features: ChatGPT’s offering is constantly evolving.

What is ChatGPT Deep Research?

Deep Research is a mode designed to handle research tasks that are more complex than a normal conversation.

Rather than simply answering straight away, Deep Research can plan a search, consult online and other available sources, analyse the information gathered and produce a structured report with citations or links to sources.

It is particularly useful when a question calls for multiple sources, comparison of information, in-depth analysis, documented research, data verification or the production of a report.

For a simple question, on the other hand, an ordinary conversation can be much quicker.

The distinction matters because it shows how ChatGPT has evolved from a simple chatbot into a platform capable of handling different ways of working depending on the objective.

ChatGPT for business: what is it for?

Businesses can use ChatGPT in virtually any activity that involves processing information, creating content, analysing data or working with documentation.

Some examples are:

The real advantage for a company, however, arises when AI is embedded within clear processes, with defined objectives, responsibilities, controls and usage rules.

What are ChatGPT’s limitations?

Despite its capabilities, ChatGPT is not infallible.

The most significant limitation is that it can generate incorrect information while presenting it in convincing language.

This phenomenon is often associated with the term “hallucination” in artificial intelligence.

A model can:

• confuse information;
• attribute a quotation to the wrong source;
• invent a reference;
• misinterpret a request;
• make mathematical errors;
• produce code that does not work;
• use outdated information when it has no up-to-date source;
• draw a seemingly logical but incorrect conclusion.

OpenAI itself warns that ChatGPT’s responses may be inaccurate, untruthful or misleading.

Why can ChatGPT make mistakes?

A response being grammatically correct does not mean it is factually correct.

The model is designed to generate a useful response based on the context and information available, not to automatically guarantee the truth of every statement.

That is why it is essential to distinguish between:

the ability to generate an answer

by

the ability to verify that the answer is true.

These are two different problems.

How to reduce errors

When the information matters, it is advisable to:

• ask for verifiable sources;
• use web search when you need up-to-date information;
• comparing multiple sources;
• check figures and quotations;
• check important documents yourself;
• test the generated code;
• do not delegate high-impact decisions to AI without oversight.

The quality of the response can improve if you also give ChatGPT the necessary context: documents, data, constraints, examples and evaluation criteria.

Does ChatGPT have access to up-to-date information?

It depends on the mode used.

A conversation with the model should not automatically be considered equivalent to a real-time search.

When the web search feature is available, ChatGPT can look up recent information online and use it to answer questions that require up-to-date data. OpenAI lists web search as one of the tools built into the platform.

The distinction matters above all for topics such as news, prices, regulations, financial data and recent company information. In these cases you also need to check when the information dates from and which source it comes from.

ChatGPT and privacy: what should you consider?

Privacy is an important consideration when using generative AI systems.

Before entering confidential information into ChatGPT, it is advisable to consider:

In a company, for example, it should not be considered normal to routinely enter contracts, personal data, financial information or proprietary documentation into a public chatbot without first checking the applicable terms.

The simplest principle is:

do not share with an AI system any information you would not be authorised to share with the specific tool you are using.

For professional use, it is also important to distinguish between personal accounts and solutions designed for organisations, because tools, administration and terms may differ.

ChatGPT and work: is AI replacing people?

The question “Will ChatGPT replace workers?” is too broad to have a simple answer.

The impact of AI depends above all on the type of activity.

A highly repetitive task, based on transforming information and with easily verifiable results, lends itself more readily to automation.

An activity that instead requires:

• responsibilities;
• human relationships;
• judgement;
• knowledge of the context;
• negotiation;
• strategic creativity;
• experience;
• managing uncertainty

still requires a very significant human role.

This is why it is more useful to speak of a transformation of work than of simply replacing people.

A professional using ChatGPT can delegate certain preparatory tasks to the AI and focus more on those that require decision-making expertise.

The objective should therefore not be:

“do the work for me”

but:

“which parts of my work can be accelerated or improved by AI without losing control and quality?”

ChatGPT and the AI Act: what does European regulation have to do with it?

The use of artificial intelligence in Europe is shaped by the AI Act, the European Union regulation that sets out a regulatory framework based, among other elements, on the risk level of systems and the related obligations.

It is important, however, to avoid a common oversimplification: it is not correct to automatically classify “ChatGPT” as a single system belonging to one risk category.

The legislation considers various elements, including the type of system, the model, the use case and the role of the operator.

In particular, the European framework also introduces specific obligations for general-purpose AI models (GPAI), while the requirements applicable to a given system depend on how it is used and on the role taken in the supply chain.

For companies and professionals, this means that compliance cannot be assessed simply by asking “Is ChatGPT compliant with the AI Act?”. Instead, it is necessary to analyse how the system is used, what data is processed, what function it performs and which obligations apply.

ChatGPT vs Gemini: what is the difference?

ChatGPT and Gemini are two of the best-known generative AI platforms, but they belong to different ecosystems.

OpenAI develops ChatGPT, Google DeepMind develops Gemini.
Both can be used for tasks such as writing, summarising and studying. The difference should not, therefore, be reduced to “which chatbot is smarter”.

The choice also depends on the ecosystem in use, the tools available, the type of task, the models accessible and the way the user works.

For example, a user deeply integrated into the Google ecosystem might place great value on features linked to Google services. A user who instead relies on tools and workflows from the OpenAI ecosystem might find it more natural to work directly in ChatGPT.

Model performance changes over time, so an absolute comparison between ChatGPT and Gemini risks quickly becoming outdated. It is more useful to compare the specific feature and the specific use case.

Is ChatGPT a chatbot or an AI assistant?

At first, ChatGPT was seen mainly as a chatbot.

Today this definition has become incomplete.

A chatbot is generally understood as a system designed to hold a dialogue with the user. ChatGPT retains this characteristic, but also includes tools for search, data analysis, images, files, voice, programming, in-depth research and complex tasks.

That is why the term AI assistant better describes the product’s current evolution.

The difference also matters in practice: a chatbot mainly answers questions; an AI assistant can help the user carry out a task made up of several steps.

How to use ChatGPT effectively

Getting better results takes more than knowing what ChatGPT can do. It is equally important to understand how to use it.

1. Define the objective

Before writing the prompt, be clear about the result you want to achieve.

Not:

“Tell me about SEO.”

Better:

“Explain how to build an SEO strategy for a commercial page aimed at Italian entrepreneurs.”

2. Provide the context

The more a task depends on context, the more useful it is to provide it.

You can specify:

• sector;
• audience;
• objective;
• tone;
• source material;
• constraints;
• quality criteria.

3. Specify the format

If you want a table, ask for a table.
Want a five-point summary? Then say so.
If instead you want a text ready for publication, always remember to specify it.

4. Refine progressively

There is no need to try to create the perfect prompt at the first attempt.
You can use the conversation to refine the result progressively.

5. Verify important outputs

ChatGPT’s speed does not remove the need for human oversight.

For strategic, legal, financial, medical, technical or business information, verification remains essential.

What is the real value of ChatGPT?

The value of ChatGPT does not lie simply in its ability to produce text quickly.

The most important change concerns the way people can interact with information and digital tools.
In the past, many tasks required knowledge of the specific software used to carry them out. With a conversational AI assistant, part of the interaction can shift from technical language to natural language.

This makes it possible, for example, to say:

“Analyse this data and explain the most significant anomalies.”

rather than necessarily having to know every function of the software used for the analysis.

The same logic can be applied to writing, programming, research, study and information management.
The real value therefore emerges when artificial intelligence narrows the gap between what a person wants to achieve and the tools needed to achieve it.

Is ChatGPT really useful?

Yes, but its usefulness depends on how it is used.

ChatGPT is particularly effective when used as a:

• writing assistant;
• brainstorming tool;
• research support;
• an accelerator of repetitive tasks;
• analysis support;
• learning tool;
• programming assistant;
• conversational interface for working with information and content.

It is less appropriate to treat it as an automatic source of truth.

The difference between superficial and professional use often lies precisely here: in the first case, the answer is taken and used; in the second, the objective is defined, context is provided, the result is checked and control over the process is retained.