What does it mean when people say an AI model is 'open' like DeepSeek?

It means the model's code and design details are publicly shared. You can download it, run it on your own computer, and even change how it works. Think of it like a recipe. A closed model, like the one inside ChatGPT, is a secret recipe you can only taste at the restaurant. An open model gives you the full recipe to cook at home. You can see every ingredient and tweak the spices. DeepSeek's latest model is a good example of this. They released a detailed paper explaining how they built it. This is different from just being 'free'. A free app might still be a black box. With a truly open model, you get the actual files. I've found this is a huge deal for businesses that can't send customer data to a third-party server. They can run the AI on their own secure machines. The downside? You need your own hardware, which can get expensive. Running a powerful model still requires a serious graphics card, not just a basic laptop. But the control you gain is often worth the cost for developers and privacy-focused users. A key insight here is that 'open' doesn't always mean the same thing. Some companies only release the model's final settings, not the data or code used to train it. This makes it hard to fully replicate their results. Always check what 'open' actually includes before you get too excited.