what are the file needed to hosting

Question

Dear Experts,

 

I published my web application on server its working fine 

 

but 

 

after that i I recently done some chages in that web application

 

here i need to update my web application at server,

so what are the files need to update 

 

or else 

 

need to do re publish?

 

how to resolve ? i'm New to this topic