ChatGPT

ChatGPT is OpenAI’s conversational interface built on the GPT-4o family of large language models. Launched to the public on November 30 2022 and continuously upgraded since, it lets people interact with advanced AI in natural dialogue—asking follow-up questions, refining requests, and getting coherent answers, code snippets, or creative drafts in seconds.

How it works

• Transformer foundations: Like its GPT predecessors, ChatGPT uses a transformer architecture trained on vast text and code corpora, then fine-tuned with human feedback to follow instructions safely and fluently.
• Multimodal GPT-4o core: Since May 2024, the service runs on GPT-4o, a natively multimodal model that understands and generates text, images, and—soon—real-time voice, replacing earlier GPT-3.5 and GPT-4 engines.
• Memory & custom GPTs: Users can enable “Memory” so the assistant recalls preferences across chats, or build purpose-specific “GPTs” that package custom instructions, knowledge, and tools for sharing or sale.

What people use it for

• Rapid brainstorming, writing assistance, and language translation
• Learning support—from math explanations to exam prep
• Software prototyping, debugging, and data analysis
• Create Image
• Customer support automation and workflow integration via the OpenAI API

Availability & tiers

A free web and mobile tier offers GPT-4o mini with message limits; ChatGPT Plus (US $20/month) unlocks higher caps, the full-size GPT-4o, and early access to new voice and vision modes. Specialized offerings such as ChatGPT Enterprise and ChatGPT Gov provide enhanced security, admin controls, and higher-throughput API access for businesses and U.S. government agencies.

In short, ChatGPT turns today’s most capable generative AI into an everyday assistant—helping millions of individuals and organizations think, create, and solve problems faster.