Models are how you automate your work. When you create a model, you are preserving a set of tasks, or a data processing workflow, that you can execute multiple times. There are an infinite number of tasks you can automate using models.
GIS users also compose and execute analytical models that help in decision making, prediction, and in understanding different scenarios.
You create models using ModelBuilder to chain together tools, using the output of one tool as the input to another tool.
The model you create is added to ArcToolbox as a model tool, which you can execute using its dialog or the Command Line window. You can also execute the model within ModelBuilder.
The first place you should start is with
Creating a simple model, which leads you step-by-step through creating and executing a working model. You can follow this example to actually create and execute the model, or you can just read the example to understand the key points.
Learn about model concepts and termsLearn more about ModelBuilder
Finally, for a bit of fun, click
here to see an example of a large complex model that does useful work. This model performs quality assurance testing on every tool in the Spatial Analyst extension. ESRI's test suite includes dozens of such models that are run on a daily basis. In practice, you would rarely want to build such a complex model—you'd want to break it up into smaller models and have a main model that uses these smaller models.