What does ngf prefix mean in angularjs and ng-file-upload?

Question

I've come across an ngf-select directive in ng-file-upload for AngularJS. It's used like

<button type="file" ngf-select="uploadFiles($file, $invalidFiles)"
        accept="image/*" ngf-max-height="1000" ngf-max-size="1MB">
   Select File
</button>

I managed to find very little info on what it stands for. I can only guess it's something like an if-condition on select event. I pretty sure I've missed some part in the docs and I don't want to get by with guessing.

Can anyone explain what do ngf prefixes do and probably give a link to documentation?

Answer 1

Well there is a lot of discussion about this but majority of people say's that The prefix ng stands for "Angular;" all of the built-in directives that ship with Angular use that prefix. Similarly, it is recommended that you do not use the ng prefix on your own directives in order to avoid possible name collisions in future versions of Angular.As like this "ngf" is the in built directive of file uploaing

And some say that ng just sounds like Angular

some may saying that ng stands for "Next Generation" as the angular is booming with its features ....

please check this

https://docs.angularjs.org/api/ng