ChatGPT

ChatGPT is the product that brought large language models to the mainstream. Launched in November 2022, it crossed 100 million users faster than any consumer application in history. Built by OpenAI, it remains the most widely recognised AI assistant and the default starting point for most people exploring AI for the first time.

What it does

ChatGPT is a conversational AI that can answer questions, write content, analyse data, generate code, summarise documents, brainstorm ideas, and handle a remarkable range of knowledge work. It supports text, image, and file inputs, and can generate text and images in response. With the introduction of GPT-4o, it handles multimodal tasks — you can upload a photo of a whiteboard and ask it to convert the notes into a structured document, for example.

How it works in practice

The free tier gives you access to GPT-4o mini and limited access to GPT-4o, which is more than enough for casual use. The Plus plan unlocks higher usage limits, the DALL-E image generator, Advanced Data Analysis (which lets you upload spreadsheets and CSVs for analysis), and custom GPTs — pre-configured versions of ChatGPT tailored to specific tasks.

The interface is clean and approachable. Conversations are saved in a sidebar for easy reference. You can create custom instructions that persist across sessions, telling ChatGPT about your role, preferences, and communication style. This is a powerful feature that many users overlook.

Where it excels

ChatGPT shines as a generalist. Its breadth of knowledge is unmatched — it can help a marketer write ad copy, a developer debug Python, a student understand calculus, and a manager draft a performance review, all in the same afternoon. The ecosystem around it is also the largest: thousands of custom GPTs, a plugin marketplace, and deep integrations with tools like Zapier, Canva, and Microsoft 365.

Where it falls short

ChatGPT can be confidently wrong. Hallucinations — plausible but fabricated information — remain a real issue, especially for factual queries where accuracy matters. The free tier now includes web browsing, though the paid tiers offer more extensive search capabilities. For tasks that require precise, up-to-date information, you may still want to verify its output or use a tool like Perplexity instead.

The conversation memory system, while improved, can still lose context in long threads. If you are working on a complex multi-step project, you may need to periodically re-state your requirements.

The business case

For individuals and small teams, ChatGPT Plus at $20 per month is arguably the highest-ROI subscription in business software. The Team plan adds workspace management, longer context windows, and admin controls. Enterprise customers get SSO, data privacy guarantees, and unlimited access to the most capable models.