Removing of specific line in text file

Question

I am working on an option which will be able to remove the line specified if the user types in the exact title and author.

However I will not be able to make it work

Answer 1

You're trying to pass a bash variable (two, actually) into a sub-program (sed), but surrounding the expression you're passing in single-quotes, which does no parameter expansion. That means that sed is literally seeing $Title:$Author. Try putting the whole sed expression in double-quotes:

sed -i "/$Title:$Author/d" BookDB.txt

This will allow bash to expand $Title and $Author before they get into sed.