Uploaded January 2026 | Updated September 2026, 1 hour ago

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Day 22/42: Proprietary vs Open Models

Yesterday, we talked about agentic AI.
Today, we choose the brain.

There are three model families:

Proprietary: powerful, easy, but closed

Open-weight: flexible, customizable

Open-source: full control, more work

ChatGPT is proprietary.
Llama and Mistral are open-weight.

This choice affects cost, privacy, speed, and control more than people realize.

Missed Day 21? Start there.
Tomorrow, we explain how apps actually talk to models: APIs.

I’m Louis-François, PhD dropout, now CTO & co-founder at Towards AI. Follow me for tomorrow’s no-BS AI roundup 🚀

#LLM #OpenSourceAI #GenerativeAI