Version control is a critical aspect of managing shared content components in DITA defense documentation. It ensures that changes to reusable content are tracked, documented, and maintained systematically. Here’s how version control is typically applied:

1. Centralized Version Control System: Defense organizations use a centralized version control system or software to manage shared content components. This system allows content authors to check content in and out, make edits, and save changes, while also keeping a history of revisions.

2. Revision History: Each shared content component, whether it’s a procedure, policy, or specification, maintains a revision history. This history includes details such as the version number, a description of changes, the author of modifications, and the date of each revision.

3. Check-In and Check-Out: Content contributors check out a content component from the version control system when they need to make changes. This ensures that only one person edits the component at a time, preventing conflicting changes.

4. Branching and Merging: In complex defense documentation projects, version control systems allow for branching and merging. This enables the creation of different branches for various document versions, such as for different defense systems or projects, and merging those changes back into the main content repository as needed.

<!– Example of version control in DITA –>

<topic id="maintenance-procedure">
  <title>Maintenance Procedure for XYZ Equipment</title>
  <metadata>
    <author>John Doe</author>
  </metadata>
  <p>This procedure outlines the maintenance steps for XYZ equipment.</p>
  <steps>
    <step>Step 1: Check for loose bolts.</step>
    <step>Step 2: Lubricate moving parts.</step>
    <step>Step 3: Conduct safety inspection.</step>
  </steps>
  <version-history>
    <version>1.0 - Initial Release - 2023-10-15</version>
    <version>1.1 - Revision - 2023-12-05</version>
  </version-history>
</topic>

In this example, version control is evident through the version history section, which records the different versions of the maintenance procedure and their associated changes.