What is an AI Model? Definition, Labs and How to Pick One

What is an AI Model? — watch on YouTube
6 min

In 30 seconds

  • ChatGPT is the app. GPT-5 is the model. Perplexity and Cursor did not build the models they run on.
  • Small models exist because large ones are slower and more expensive, so match the tier to the job instead of defaulting to the biggest.
  • Intelligence, speed and cost are a triangle. You get two of the three.

An AI model is a system trained on a huge amount of text that predicts what comes next. The app is what you type into. The model is what answers.

ChatGPT is an app built on top of the GPT-5 model. The Claude desktop app sits on Anthropic’s model. The model is the intelligence layer, where the thinking happens and where information gets retrieved.

Is ChatGPT the same thing as GPT-5?

No. ChatGPT is the app, GPT-5 is the model underneath it. Three or four years ago ChatGPT was a category of one, so nobody had to keep the two names apart. Now you have Claude, Gemini and Chinese models like DeepSeek, and people use the word “model” for the apps too.

Some apps are built by the lab that built the model. ChatGPT by OpenAI, the Claude app by Anthropic. Others take a model from OpenAI or Anthropic and build a narrower product on top of it. Perplexity and Cursor work that way. Those are wrappers, and they get their own lesson next.

Which companies actually build the models?

Five labs.

Lab Models What to know
OpenAI GPT-5, GPT-5 mini, o-series The leader in the space. GPT-5 is the largest and smartest, mini is the cheap small tier, and the o-series are the reasoning models. None of them are open weight, so you cannot download one and run it yourself.
Anthropic Haiku, Sonnet, Opus Smallest to largest, one family. Most people run Sonnet as the daily driver.
Google Gemini Flash, Gemini Pro Flash is the one you point at a queue of after-hours messages that all have to be sorted before 9am. Gemini Pro takes the harder thinking and takes longer over it.
Meta Llama series Open source by default. Any engineer or any company can download it and run it on their own hardware.
xAI Grok An up and comer. Not used as much as the other four.

DeepSeek is the Chinese model that comes up most in these conversations. It is not one of the five above.

Is a model the same as an LLM?

An LLM, a large language model, is one kind of model. It is the kind that reads and writes text, and it is the kind every name in that table refers to. There are also models that only handle images, and models that only handle speech. The big labs now ship single models that take text, images and audio together, which is what multi-modal means.

Why every lab sells a small model

Larger, smarter models are slower and more expensive. That is the whole reason the tiers exist.

Sorting an after-hours message into emergency or not emergency is a yes or no question over a short block of text. Cleaning up a transcript is the same class of job: the answer is nearly determined by the input, and there is nothing to work out. Neither one needs your most expensive model. Complex thinking across several sources arriving at once is what the big model is for.

What you save on a small model is a per-token rate. The same ten-page document is the same number of tokens whether Haiku, Sonnet or Opus reads it. What changes is the price you are charged for each of those tokens, which is why running every job on the top tier costs far more than the work is worth.

The framework for choosing is a triangle with intelligence, speed and cost at the corners. You get two.

  • Smart and cheap, and it will be slow.
  • Cheap and fast, and it will not be that smart.
  • Smart and fast, and you will pay for it.

So ask how much intelligence the job needs, how fast it has to finish, and what you are willing to pay. Asked in that order, most jobs answer themselves. After-hours triage runs all night, has to reply before the caller gives up, and comes down to one yes or no call, so it lives on the cheap fast tier and stays there.

How do you know which model is best right now?

Look at a leaderboard. We use LMArena, a table of models ranked by category, writing for example, based on testers voting on which output they preferred.

Do that once, not weekly. Two years ago you had to keep up, because the gap between the models was large enough to change what you could build. Today they are all pretty good, and the labs compete on the tools they build around a model more than on the intelligence inside it.

So pick a tier per job. The cheap fast model for the high-volume triage work, the big one for the handful of calls where being wrong costs you a truck roll.

Full transcript

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Hey, my name is Mahan. I'm the CMO of Nairon. My name is Luka. I'm the CEO of Nairon. Luka, when Chad GBD first came out around 3 to four years ago, it was pretty much a category of one. Definitely. Now, fast forward 3 to four years, we have all these new models on the market.

You have Claude, you have Gemini, you have Chinese models like Deepseek. So in this video, break down for us exactly what an AI model is and what should people you know know in order to make the right decision on what to use, when to use it.

So essentially the model is the engine behind some of our favorite tools like Chach PT for example. I think it's important to distill this down that the model is the intelligence layer behind all of these tools, right? It's where a lot of the thinking happens. It's where the actual retrieving of information is happening, right? And our favorite tools like ChatGPT, like claude, like cursor and perplexity that we have here essentially are just built on top of the models themselves. So for example, ChatGPT is an app that's built on top of the GPT5 model for example and claude the app the co-working space that we that we like to use on our desktops that is built on top of the uh model itself, right? The cloud model, Anthropics model and then we have other rappers that are built by other companies. So not built by the actual labs themselves like Anthropic and OpenAI but rather like Perplexity Cursor. These guys are essentially rappers. They've built a product on top of the model themselves.

And rappers are things we'll get into in the next episode as well. For the time being, I think it's just to simplify it. It's a company that uses the model from OpenAI Anthropic in order to make another more nuance product.

Yeah, definitely. And so if we look at what all of the model providers are like what the landscape is, you have really five big players here. You have OpenAI. They are essentially the leader in the space. As you can see over here, we have three different models. We have the GPT5, we have the GPT5 mini and the O series. The GPT5 essentially is the smartest, largest model. The mini is a smaller model. And we'll get into why there are different models per company.

Um, but when looking at the O series, the O series is actually their open- source model, right? So essentially you can run the model on your own machine. And so looking at the anthropic models, you obviously know Opus. They also have the Sonnet and Haiku models. Those are smaller models. At Google, they have the Gemini Pro and the Gemini Flash, a very smart model, but they're also a very fast model. And then at Meta, they're more open- source. They try to do things that's available for any engineer to run and any company to run. And so they have the the O Llama and the Llama series.

And then you have Grock, right? It's a up and cominging AI lab. They're not used as much as the other four, but still an upandcomer in the space. And so why wouldn't just someone always use the most powerful model? Why do these tiers even exist?

So the tiers exist because the larger, more smarter models are slower and more expensive. And so if you have a very simple task like you want to clear up a transcript or you just want to identify a yes or no question from a simple block of text, you would most likely use the cheaper models for that type of stuff.

But if you wanted very complex thinking, a complex answer to a plethora of data sources coming in, you would use the biggest model. So here we're looking at anthropics three models, haiku being the smallest one and opus being the largest one. A lot of people actually use Sonnet as like the daily driver and also the biggest difference is the token usage drastically varies between all three of them.

And so what kind of mental framework should I use when picking out a model for a specific task? So the mental model that I like to have is this triangle where you either choose two out of the three um bases of the triangle. you either have the capability or how smart a model is with how expensive it is, but you lose out on speed or you look at a cheap and fast model, but it's not, you know, that that smart. And so you can really only have two out of the three available options.

And so when thinking about your task, we like to think about how much intelligence is needed, how quick does this operation need to get done, and how much budget can I set for the specific task. Obviously with how fast the space is advancing, you're seeing all these companies release new models, constantly compete with each other. So how can the average consumer know exactly which model is the best at the specific task that are looking to get done? So in order for you to really uh understand which model to use for which use case, you would essentially need to look at like a leaderboard. And so we love to use arena.ai. It's essentially a table similar to this one. This is a simplified version, but it essentially shows you in writing these models are out competing and they're done by peer-reviewed literature. So, a bunch of testers are voting on, you know, what has the best outcomes. In general, the models are pretty good and perhaps we don't need to really stress too much about this. This was the case more about 2 years ago where you really had to know this because there was such a big difference between the models. And so the larger labs are essentially building tools on top of the models to differentiate themselves rather than the intelligence of the models themselves like rappers of course.

And so guys, we'll cover rappers much more in depth in the next video. In the meantime, you can subscribe to our newsletter links down in the description below. You can also find us on LinkedIn where we're very very active. And uh we'll see you next time.

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