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Are Java generators primarily a way to enforce a static type on collection items?

private ArrayList<String> colors = new ArrayList<String>();

Looking at the example above, it seems that the main motive of generics is to force the use of a type in a collection. Thus, instead of having an array of "Objects", which must be attributed to String at the discretion of the programmer, I use the type "String" in the collection in ArrayList. This is new to me, but I just want to check if I understand it correctly. Is this interpretation correct?

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List myIntList = new LinkedList(); // 1
myIntList.add(new Integer(0)); // 2
Integer x = (Integer) myIntList.iterator().next();  // 3

Generics

List<Integer> myIntList = new LinkedList<Integer>(); // 1'
myIntList.add(new Integer(0)); // 2'
Integer x = myIntList.iterator().next(); // 3'

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