# Content controls

> Use structured DOCX regions for fields, clauses, repeating content, and application-owned workflows.



Content controls are structured regions stored as `w:sdt` elements in a DOCX. They let your application find and change
document content by metadata instead of matching the visible text.

**Content-control shapes**

| Shape | Wraps | Common use |
| --- | --- | --- |
| Inline | Part of a paragraph | Repeated values and typed inputs |
| Block-level | Paragraphs or tables | Clause slots and document sections |
| Repeating section | A collection of items | Line items and repeated records |


## Choose a workflow [#choose-a-workflow]

- [Add fields to a DOCX template](/editor/content-controls/add-fields-to-a-docx-template): Turn selected content into tagged inline and block-level fields.
- [Fill a DOCX template](/editor/content-controls/fill-a-docx-template): Connect application data to repeated values and typed controls.
- [Replace clauses from your application](/editor/content-controls/replace-clauses-from-your-application): Use tagged block-level fields as application-managed clause slots.
- [Lock template fields](/editor/content-controls/lock-template-fields): Keep a field, its contents, or both from being changed during normal DOCX editing.


Beyond these workflows, content controls support:

* **Typed inputs:** Use text, checkbox, date, and choice controls for values with known input behavior.
* **Repeating records:** Add, clone, and remove repeating-section items for lists such as line items or questionnaire
  responses.
* **Custom field UI:** Build a field list, navigation panel, or workflow around the controls in the open document.

Use the [Document API reference](/document-api/reference/content-controls/) for the complete operation set. Use
[custom content-control UI](/editor/custom-ui/content-controls) to connect document selection and navigation to your
application.

## Identify a control [#identify-a-control]

Use a tag as the application lookup key. The alias gives people a readable title, while the ID identifies one occurrence
inside the document.

| Word property | SuperDoc value     | Use it for                                                                                  |
| ------------- | ------------------ | ------------------------------------------------------------------------------------------- |
| Tag           | `properties.tag`   | Connect one application field to every matching control. Multiple controls can share a tag. |
| Title         | `properties.alias` | Show a human-readable field name in Word or your application UI.                            |
| ID            | `id`               | Address one occurrence of the field in the DOCX.                                            |

A shared tag groups controls for lookup. It does not synchronize their content. Your application decides how values flow
between its data and each document occurrence.