6. Functions that always return

In this Chapter 6, I'll show you functions that always come back, while they are very powerful.

From array to string and vice versa 

1. Split
2. Join
Manipulating all array elements at once 
3. Map
Filter array elements 
4. Grep
Filter and manipulate the returned array elements 
5. Grep & map
Filter and manipulate the returned array elements 
6. Sort & subroutines