MongoDB | understanding the logic behind the output of print(db.collection)

Question

I'm working with MongoDB currently, and I'm trying to understand this output:

I created a DB called test and a collection called coll, and inputed this command:

print(db.coll)

it prints

test.coll 

Which I know is the name of the DB and the collection. After I add documents to the collection, if I type into the shell db.coll again, it still prints test.coll. What I want to know, is whether it's still supposed to output only test.coll even if I added documents.

What does print(db.coll) actually mean?

Thank you in advance!