Ruby/Array/include

# The include? method returns true if the supplied parameter is in the array, 
# and false otherwise:
 
x = [1, 2, 3]
puts x.include?("x")
puts x.include?(3)

year = [2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009]
 
year.include?( 2010 ) # => false

year = [2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009]
 
puts year.include? 2004 # => true