you should avoid global variables
you should declare functions safely
you should use parseInt correctly
you should understand strict comparison
you should be able to determine the location of an item in an array
you should be able to add the values of an array
you should be able to remove a value from an array
you should be able to add an item to the end of an array
you should be able to remove the last item of an array
you should be able to join together two arrays
you should be able to add an item anywhere in an array
you should be able to count the occurences of an item in an array
you should be able to square each number in an array
you should be able to find all occurrences of an item in an array