1. splice(), slice() methods
(1)、arrayObject.splice(index,howmany,item1,.....,itemX)
Add/remove items to/from an array, then return the removed item
Note: This method will change the original array
(2)、arrayObject.slice(start,end)
Returns the selected element from an existing array
Returns a new array containing the elements in arrayObject from start to end (excluding this element)
Note: This method does not modify the array, but returns a subarray