first

Returns the first character. If a limit is supplied, returns a substring from the beginning of the string until it reaches the limit value. If the given limit is greater than or equal to the string length, returns self.

str = "hello"
str.first    # => "h"
str.first(1) # => "h"
str.first(2) # => "he"
str.first(0) # => ""
str.first(6) # => "hello"