JS Array method Summary array array element additions and deletions

Unshift: Adds a parameter to the beginning of the original array and returns the length of the array
Pop: Deletes the last item of the original array and returns the value of the deleted element, or returns undefined if the array is empty
Push: Adds a parameter to the end of the original array and returns the length of the array
Concat: Returns a new array that adds a parameter to the original array.
Splice (Start,deletecount,val1,val2,...) : Deletes the DeleteCount entry from the start position and inserts the Val1,val2 from that location,...
Reverse: Reverse-order the array
Sort (orderfunction): Sorting by specified array of parameters
Slice (Start,end): Returns a new array of items from the original array specifying the start subscript to the end subscript