Difference between an 'extension' and 'add-on' in Google Docs

[te2]

I have a Google Apps Script that performs functionality that needs to be available to a very limited number of users internally (2 or 3 for now). I have created a GWS add-on from an App Script before so I am somewhat familiar with the process, however it feels wrong to create an entire add-on for functionality that would only be used by a very limited number of people. 

On the toolbar in Google Docs, there is an 'Extensions' option. I am trying to explore if creating an extension would be a better option, however I am struggling to understand the difference between an extension and add-on. Anything I google seems to come up with answers for browser extensions instead of Docs extensions. 

I was wondering if anyone knows the differences and what would be the best way forward given my requirement above? Should I just create an add-on and make it internal only?

[anothercharles · Accepted solution]

Hey te2,

The difference between a Google Workspace Add-on and "Extension" can be a bit confusing :s  They are similar, but different in a number of ways. Typically something published for others to use is a Add-on and they can of course be shared to the external marketplace as well as the internal-your-org-only. But if you look under the "Extensions" menu, there is also an "Add-ons" sub menu - so are they "extensions" too? 

Well first fact about Add-ons in Google with Workspace is there are two distinctly different ways to build them. Editors Add-ons and Google Workspace Add-ons: https://developers.google.com/apps-script/add-ons/concepts/types These each let you program differently against Workspace but to achieve essentially the same results - 'extending' the apps to do more with them, and normally you share - aka publish - them to the marketplace. 

That said, you can still use the framework of either Editor or Workspace Add-ons and NOT publish and still use them fully.  You get the ability to create menu with (older) Editor add-on framework, or side panels using the Card Builder with (newer) Workspace Add-on framework, but don't need the hassle of publishing, which sounds advantageous in your case, which you mentioned only a couple of users who you work with internally. While publishing an add-on makes sense typically for seamless distribution, its often overkill for just a couple of other users who may just benefit from sharing the file with the Apps Script code bound to it. If you are working in say just Docs or Sheets, I would tend to use an Editor add-on type of project and just share it. But if the documents are going to be copied to new versions by your users, note your code will be too! so then you really would be better off publishing either add-on type (editor or GWAO).

In summary, an extension isn't always an add-on - can be any App Script project you run with a Doc or Sheet. It becomes an add-on when you use the either Editor or Google Workspace Add-on framework to build it, and then to publish it. So like I mentioned, they are really similar, with some nuanced differences. This section of the developer docs is a great place to understand it all .... https://developers.google.com/apps-script/add-ons/overview   

[te2]

Thank you anothercharles. Fantastic, well-written explanation. This has cleared it up quite a but for me!