Where are the reference documentation to Widgets?

[emad]

Im new to Lithium and I'm suppose to edit and reskin a community.

I see in the SDK that some components reference already existing widgets such as 

<component id="common.widget.page-title"/>

or 

<component id="forums.widget.recent-threads"/>

So I was just wondering where can I see widgets there are for forums or the common ones?

Thank you

[Payal]

@emad  -  You can get all the OOTB component list(Global, Forum, Blog) in Studio under the Page Tab. 

Reference SS:

Please let me know if this helps.

Thanks