Every time ChatGPT gets an upgrade, it’s news. But what exactly is ChatGPT?
ChatGPT is OpenAI’s flagship AI model. In August 2025, the company unveiled GPT-5, its latest iteration. OpenAI CEO Sam Altman says GPT-5 is its most advanced AI model yet, marked by increased general intelligence and enhanced usability, like a “real-time router” that selects the most appropriate model to handle each user request.
Here’s everything you need to know.
What is ChatGPT?
OpenAI is the leading AI startup. Its ultimate mission is to develop artificial general intelligence, or AGI, in a way that benefits humanity as a whole. AGI is a still-theoretical AI that reasons as well as humans.
The company first released ChatGPT in November 2022. It has yet to achieve AGI-level intelligence. For now, it’s a conversational chatbot that relies on a large language model to generate responses to questions. Some people use it much like they would Google Search. But it can also do deeper research, generate images and reports, write just about anything, code, and solve problems that involve quantitative reasoning.
Since its debut, the chatbot’s user base has exploded. OpenAI said in a blog post in August that its user base had reached 700 million weekly users.
How to use ChatGPT
ChatGPT is available online, and as an app available for both iOS and Android.
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Users engage with it through conversation by simply typing in a prompt — an instruction for the chatbot. OpenAI also unveiled an “advanced voice mode” in 2024 — following a legal battle with Scarlett Johansson over the use of a voice that sounded too similar to hers — that lets users engage with the chatbot in natural, real-time conversations with the ability to sense emotions.
Since the release of ChatGPT, OpenAI has unveiled several different ChatGPT models — all of which can be used in conjunction with the chatbot. It has rolled out a series of reasoning models, for example, which are designed to think more deeply about problems. It also unveiled GPT-4.5, which Altman described on X as “the first model that feels like talking to a thoughtful person.”
Until the release of GPT-5, it was up to the user to understand which model was best for their needs. Now, GPT-5 can make that decision for them. That means, in essence, that the model is deciding how long it needs to think about a problem to get to the best answer.
ChatGPT also offers dozens of plug-ins to paying subscribers. An Expedia plug-in can help you book a trip, while one from OpenTable will nab you a dinner reservation. OpenAI has also launched Code Interpreter, a version of ChatGPT that can code and analyze data.
Despite the bot’s impressive capabilities, it remains imperfect. ChatGPT relies on available data for its responses, which means it can sometimes give misinformation. OpenAI has also been accused of stealing personal or copyrighted data to train ChatGPT. It has even encouraged students to cheat and plagiarize on their assignments.
How does ChatGPT work?
Chatbots like ChatGPT are powered by large amounts of data and computing techniques to make predictions and string words together meaningfully. They not only tap into a vast amount of vocabulary and information but also understand words in context. This helps them mimic speech patterns while dispatching encyclopedic knowledge.
When a user prompts a large language model, the query is broken into tokens — the smallest unit of text a model processes. For OpenAI’s models, they can be “as short as a single character or as long as a full word, depending on the language and context. Spaces, punctuation, and partial words all contribute to token counts,” according to OpenAI.
ChatGPT’s growing influence
Users have flocked to ChatGPT to improve their personal lives and boost productivity. The chatbot attracted 100 million users in its first five days on the market, a record at the time.
Some workers have used the AI chatbot to develop code, write real estate listings, and create lesson plans, while others have made teaching the best ways to use ChatGPT a career in itself.
Businesses, including consulting firms, are also scrambling to adopt AI. The popularity of ChatGPT crystallized the value of a conversational tool, McKinsey senior partner Delphine Zurkiya told Business Insider.
“There wasn’t a major shift in our strategy in the sense that we had already been developing a lot of tools internally. It’s just these tools now have become, we’ll say faster, in delivering value thanks to that natural user interface,” she said in regards to the firm’s internal chatbot, Lilli. Many consulting firms are also building similar tools for clients. KPMG, for example, has been collecting data on how its workers prompt AI, and used that information to build new tools — for itself and clients.
AI is also making waves in the legal world. Gibson Dunn is piloting ChatGPT Enterprise for its roughly 500 lawyers and staff. Judges, however, say they’ve seen an increase in fake legal citations due to lawyers relying too much on AI.
There is a slate of ChatGPT competitors that have also come out since its launch. Meta AI, built on its Llama 4 model, offers users an AI assistant that “gets to know” user preferences, remembers context, and is personalized. Anthropic’s Claude has become the leading AI assistant for coding. Elon Musk also built Grok, a chatbot that the company is training in line with Musk’s support for free speech. Google has Gemini, a multimodal model that CEO Sundar Pichai called “one of the biggest science and engineering efforts we’ve undertaken as a company.”
For OpenAI, which continues to unveil new models at a healthy clip, the chatbot is an eternal work in progress.
“There is no analogy for what we’re building,” Nick Turley, the company’s head of ChatGPT, said on a podcast in August.
