Summary: How to prevent pipelines to trigger in Azure DevOps Server 2018.
Date: Around 2020
Refactor: 29 April 2025: Checked links and formatting. Rebranded Team Foundation Server (TFS) to Azure Devops Server.

If you're working with Getting Started With Azure DevOps Server 2018 and have enabled Continuous Integration it could be considered undesirable that an automatic build is run each time you make a change. For example, if you only changes some comments you don't have to run a build to know it's still working. If you'd need that, simply add ***NO_CI*** to the comment to prevent the build from starting. It is enough to add the section, you don't have to replace the entire comment section. So for example,

Changed file powerscript.ps1, added some comments. ***NO_CI***

will simply work.
If you're working with a build file you can also use the $(NoCICheckinComment) property in the build file.

See here for even more options.