In Ruby, a String is created with double-quotes:
"I am a String"
String interpolation is done in Ruby with # { }:
new_string = "New"
"I am a #{new_string}"
Return the lowercase version of a String:
"I am a String".downcase
Replace any substring of String that matches “\r” with a space:
"I\ram\ra\rString".gsub("\r", " ")
Replace any substring of String that matches a Regular Expression with a space:
"fallacy".gsub(/[^a]/, " ") # Regular expression