Where can I find a list of all JIRA/confluence icons and their meanings?

Question

I have found in JIRA and confluenec very different kind of icons:

a)  
            b)          c) 
           d)

Where can I find a list of all the  available icons and their meanings.
Is there a special system, why and when to use kind a),  b)  c) or  d)?

Where can I find all these Icons to use them; may be as *.png's or in a Icon-font?

And, last question: We would like to create new Icons from kind a) for our own purpose. Is there a style guide for designing them.

I have found only a list for b) here: 
https://docs.atlassian.com/aui/8.1.0/docs/icons.html?_ga=2.204300816.1886806092.1547650466-523829944.1532608551

Thank you very much for your help.

David Leal_28ge8x · Answer

@Joachim Weichert the link you shared doesn't have all the icons you can assign for different issue types.  How to download or use the copy link?, it is not an HTML URL. My intention is to use the icon image for a given issue type in a confluence page, it seems to be an easy task, but it doesn't. Thanks for any help.

maxbarrass · Answer

There is this https://www.atlassian.com/company/news/press-kit

is this the list, what about latest Jira icon?

maxbarrass · Answer

is it possible just to have an actual definitive/official list of SVG's that represent each product somewhere so that we can just download them? One per product so that we don't need to figure out why.