The answer is incremental backup as this is the one
responsible of having to provide a backup with files that are modified since
the last backup it has received, it is considered to be a backup in which is a
type of security copy.
Search engines are programs that search for and identify items based on a user input keyword, phrase, etc. Examples include google, bing, etc.
Every recursive function should have an exit criterion (=handling the base case) to exit the recursion.
Without it, it wil recurse forever, until system resources run out (typically the call stack will overflow and your program will crash).
It kinda depends on what you mean by special characters
