Everything the five big AI assistants launched between July and October 2026, explained for people who use them, not for programmers. Two lessons per platform: first the new models and what changed, then what you can actually do with them. Claude: Opus 5, Fable 5.1, the Claude 5.5 family and Cowork in every conversation, with designs, decks and docs. ChatGPT: GPT-5.6 Sol, Terra and Luna, GPT-6 with Intelligent UI, dots and the new ways ChatGPT shops, books and works for you. Grok: versions 4.5 to 4.7, Imagine for video and images, Grok Bot and The X Subscription. Gemini: 3.6 Flash, Gemini 4 Argon, Nano Banana 2.1, Skills and the Windows app. Meta: the Muse models, Meta AI that acts, and Muse, the personal agent. Every fact comes from the companies' own announcements, with dates, and the course says clearly what is still only available in the US.