array_unshift() - (aka Prepend ;; InsertBefore ;; InsertAtBegin )
array_shift() - (aka UnPrepend ;; RemoveBefore ;; RemoveFromBegin )
array_push() - (aka Append ;; InsertAfter ;; InsertAtEnd )
array_pop() - (aka UnAppend ;; RemoveAfter ;; RemoveFromEnd )
