Hi.   Hope all well.    Can someone please point me in the direction of a discussion on subscribing to equities and how this differs from the universe approach.

I am working with an exampe algo and in the Alpha the code subscribes and unsubscribes to equities that have been either removed or added.

Just trying to figure out how this all works.

My working assumption is that (under Frame work approach)

a) I can manually subscribe to an equity.  Data for this equity will then be passed to my Alpha. I can then manually unsubscribe.      items in my 'universe' i.e. subscribed equities will kept in the securities object.

b)  I can use a universe filter.   Coarse/Fine.   Anything coming out of here is kept in the securities object.   Any added or removed (changes) are passed to the Alpha along with any updates.     I presume these are subscribed to items so can unsubcribe manually if desired 

Generally, bit confused on the broader architecture re the Framework and how data is passed around - documentation not providing a super clear answer - might be there but scattered.  Have similar issues for how insights are handled.

If anyone could spend 5 mins to give very high level explanation would be really appreciated!