Slice

The slice() method is a non-mutating method that extracts a section of an array and returns a new array containing the extracted elements. It acts like a "copier" for a specific portion of the original array.

Syntax: 

array.slice(startIndex, endIndex);

• Creates a new array, leaving the original one unmodified.
• Takes two optional arguments: startIndex (inclusive) and endIndex (exclusive).
• If startIndex is omitted, it defaults to 0 (beginning of the array).
• If endIndex is omitted, it extracts elements until the end of the array.
• Negative values for indices are allowed and count from the end of the array.

Imagine you have a list of numbers as given in the numbers array. Here's how slice() comes in handy:

let numbers = [ 1, 2, 3, 4, 5, 6 ];

let newArray = numbers.slice(1, 4);

console.log(newArray); // Output: [ 2, 3, 4 ]

In above example, it starts extracting element from 1 index and stops at (4-1) index.