A broad label for different kinds of software
An email filter that spots spam, a system that recommends a film, and an assistant that drafts a reply can all be called AI. They solve different problems and do not work in exactly the same way.
Many current AI systems use machine learning: software learns patterns from examples and applies them to new input. Other approaches use rules, search, or combinations of techniques. Generative AI is the part that creates content, such as text, images, or audio.
A model is one part of a product
An AI model is the trained component that takes input and produces an output. An AI application wraps a model in software that collects a request, supplies useful context, displays a result, and may connect to other tools or data. A chatbot is an application; the language model it calls is one component of that application.
Calling something AI does not tell you how accurate, autonomous, or safe it is. The useful questions are what task it performs, what information it can access, how its output is checked, and what happens when it gets something wrong.