> For the complete documentation index, see [llms.txt](https://library.xrguild.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://library.xrguild.org/timeline-of-xr.md).

# Timeline Of XR

It is often difficult to determine when or where specific terms or products first appeared in the XR space. The XR Guild has attempted to catalogue as much of this information as possible in our interactive [Timeline Of XR](https://www.xrguild.org/timeline).

The timeline, in addition to being informative, also accepts user submissions. Below is an example of the timeline, please do visit the page to see the latest additions!

<figure><img src="https://2638478414-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FETLp7sBCPrP161DIcwQP%2Fuploads%2FW9b5pi6gWzWxjNvguGTD%2FScreenshot%202026-04-30%20090708.png?alt=media&amp;token=ce051307-7743-4e7e-a811-6260046f4131" alt=""><figcaption></figcaption></figure>

Special thanks to Avi Bar-Zeev, who created an original PDF of XR terminology which inspired this project.


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