Nginx docker advantages

Hello,
I’m new to docker. what are the advantages/disadvantages of install nginx docker instead of nginx package?

Just to be sure, is this a “I have no idea how docker works, but let me take nginx as an example” sort of question?

You might want to share your use case and pick topics from that particular use case.

Yes, exactly.
I’m just trying to test and get familiar with docker.
I want to learn how does it work

May I suggest this excellent free self-paced training? Introduction to Containers