Claude
AnthropicAssistant focused on careful reasoning, long documents and writing
by OpenAI
General assistant for writing, analysis, images and research
ChatGPT is the most widely used general assistant, covering writing, analysis, coding, image generation, document and image understanding, voice conversation and web-connected research in one interface. Persistent memory carries preferences between conversations, projects group related work with their own files and instructions, and custom versions can be configured for repeated tasks. Connectors read from services such as email, calendars and cloud storage on paid tiers, and an agent mode can carry out multi-step tasks in a browser environment. It suits almost any knowledge work task where breadth matters more than specialisation, and it is usually the default recommendation for someone adopting a single assistant. The limitations are reliability and disclosure: it still states incorrect details fluently, the free tier drops to weaker models once limits are reached, and enterprise-grade data handling requires the business tiers rather than the consumer plans.
Sign up at chatgpt.com with an email or Google account and use it free; paid tiers raise message limits and unlock the stronger models, longer research runs and connectors. For anything beyond a quick question, start a project rather than a loose chat, attach the relevant files, and write project instructions describing your role, audience and preferences, because that context is what separates useful answers from generic ones. Use deep research mode for tasks needing sources, and check the citations rather than trusting the summary. Voice mode is worth trying for thinking out loud. Two settings deserve attention early. Memory accumulates details across chats and can carry stale preferences into new work, so review and prune it occasionally. And data controls determine whether your conversations may be used for training, which matters if you paste anything confidential. Free accounts silently fall back to a smaller model when limits are hit, which explains sudden drops in answer quality.
Assistant focused on careful reasoning, long documents and writing
Google's assistant, connected to Search, Workspace and Android
Assistant built into Windows, Microsoft 365 and Edge
Answer engine that cites its sources for every claim