What have in mind when they say that it need to store password hash in the database?

It means that you don't store user password in plain text as user entered it on registration, instead hash the password with an irreversible hash algorithm such as MD5 and save this value to database.

Depending on how secure you need your users' passwords to be, then you may need to use cryptographic salt and stretching as well.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.