# Overview

> Using a Document Understanding<sup>TM</sup> ML package involves these steps:

## About ML packages

Using a Document Understanding<sup>TM</sup> ML package involves these steps:

* Collecting document samples and the requirements of the data points that need to be extracted.
* Labeling documents using Document Manager.
* Downloading or exporting labeled documents as a Training dataset and uploading the exported folder to AI Center Storage.
* Running a Training Pipeline on AI Center.
* Deploying the trained model as an ML Skill in AI Center.
* Querying the ML Skill from an RPA workflow using the [UiPath.DocumentUnderstanding.ML](https://docs.uipath.com/activities/other/latest/document-understanding/about-the-documentunderstanding-ml-activities-pack) activity package.
  :::note
  Remember that using Document Understanding ML Packages requires that the machine on which AI Center is installed can access `https://du-metering.uipath.com`.
  :::
  :::important
  When creating a UiPath.DocumentUnderstanding.ML.Activities Package in AI Center, the package name should not be any python reserved keyword, such as `class` , `break`, `from`, `finally`, `global`, `None`, etc. Note that this list is not exhaustive since the package name is used for `class <pkg-name>` and `import <pkg-name>` .
  :::

These are out-of-the-box Machine Learning Models to classify and extract any commonly occurring data points from semi-structured or unstructured documents, including regular fields, table columns, and classification fields, in a template-less approach.

![Screenshot describing the ML Packages interface in AI Center.](https://dev-assets.cms.uipath.com/assets/images/document-understanding/document-understanding-screenshot-describing-the-ml-packages-interface-in-ai-center-465442-43619efa-5e6b1a67.webp)

:::note
Out-of-the-box Machine Learning Packages that are delivered by UiPath® have version 0 and are already available on your tenant, meaning that there is no need to download them.

Download is available only for versions 1 or higher, that were already trained by you.
:::

## Types of ML packages

Document Understanding contains multiple ML Packages split into five main categories:

* [Document Understanding](https://docs.uipath.com/document-understanding/automation-suite/2024.10/classic-user-guide/document-understanding-ml-package#document-understanding---ml-package)
* [Document Classifier](https://docs.uipath.com/document-understanding/automation-suite/2024.10/classic-user-guide/documentclassifier-ml-package#documentclassifier---ml-package)
* [ML Packages with OCR Capabilities](https://docs.uipath.com/document-understanding/automation-suite/2024.10/classic-user-guide/ml-packages-ocr-capabilities#ml-packages-with-ocr-capabilities)
* [Out-of-the-box Pre-trained ML Packages](https://docs.uipath.com/document-understanding/automation-suite/2024.10/classic-user-guide/out-of-the-box-pre-trained-ml-packages#out-of-the-box-pre-trained-ml-packages)
* [Other Out-of-the-box ML Packages](https://docs.uipath.com/document-understanding/automation-suite/2024.10/classic-user-guide/other-out-of-the-box-ml-packages#other-out-of-the-box-ml-packages)