What is the purpose of the dot (.)?  I thought the current working directory would be assumed, if you don't specify the home directory?

What is the difference between the home directory and the login directory?

I feel a little confused about where the files that use the mv command go and I am unclear about the tarfile 

Can I get a clarification on what 'ls -l' means as opposed to just doing 'ls'? It appeared kind of far down on the Unix reading page.

What does 'ls -l' do? I'm also still a bit confused on "rm dir" vs "rm -r dir"... what does it mean to recursively delete, like within the specified directory to delete until everything is gone? Also could you explain the difference between "~/" and "~user/" again? Is it just that with the second one, you can specify which user you want, and the former is just for your own home?

In what cases would it be reasonable to use rm -r dir if it is worse than utilizing rm? 

How do you recover an accidentally deleted file or folder?

Still a little confused on the difference between ~ vs. ~username

I'm still a little unsure about how relative pathnames/ways work. 
 
I'm still unfamiliar with tar. Is changing file name similar to shallow/deep copy in Python? 

NA, I hope we can have more examples of new concepts in class to gain a better understanding of the materials