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# Ruby Iterators Simply put: iteration means doing the same thing repeatedly, so an iterator is used to do the same thing multiple times. Iterators are methods supported by _collections_. An object that stores a group of data members is called a collection. In Ruby, Arrays and Hashes can be called collections. Iterators return all elements of a collection, one after another. Here we will discuss two iterators, _each_ and _collect_. ## Ruby _each_ Iterator The each iterator returns all elements of an array or a hash. ## Syntax collection.each do |variable| code end Executes _code_ for each element in the _collection_. Here, the collection can be an array or a hash. ## Example #!/usr/bin/ruby ary = [1,2,3,4,5]ary.each do |i| puts i end [Try it »](#) The output of the above example will be: 12345 The _each_ iterator is always associated with a block. It returns each value of the array to the block, one by one. The value is stored in the variable **i** and then displayed on the screen. ## Ruby _collect_ Iterator The _collect_ iterator returns all elements of a collection. ## Syntax collection = collection.collect The _collect_ method is not always associated with a block. The _collect_ method returns the entire collection, regardless of whether it is an array or a hash. ### Example ## Example #!/usr/bin/ruby a = [1,2,3,4,5]b = Array.new b = a.collect{ |x|x } puts b [Try it »](#) The output of the above example will be: 12345 **Note**: The _collect_ method is not the correct way to copy an array from one to another. There is another method called _clone_, which is used to copy an array to another array. When you want to perform some operation on each value to get a new array, you typically use the collect method. For example, the following code will generate an array whose values are 10 times the values in a. ## Example #!/usr/bin/ruby a = [1,2,3,4,5]b = a.collect{|x| 10*x} puts b [Try it »](#) The output of the above example will be: 1020304050