Where do I find information on Templates?

[Codger]

I'm trying to create a frame for a tab control:
I was looking at an old addon and found this code:

local tabButton = CreateFrame("Button", nil, frame, "TabButtonTemplate")

...but when I load the addon I get an error:
CreateFrame(): Couldn't find inherited node "TabButtonTemplate"
I discovered this documentation that shows the template is available?
https://www.wowinterface.com/forums/...ad.php?t=40444
I'm still learning addon development.
Any help is much appreciated.