The `push()` method adds one or more elements to the end of an array in JavaScript.
For example, `const fruits = ["apple"]; fruits.push("banana", "orange");` leaves the array as `["apple", "banana", "orange"]`. The method changes the existing array rather than creating a separate array, and it returns the array’s new length. That return value is useful when code needs to know how many elements the array now contains.
`push()` accepts zero or more arguments, so several items can be appended in one call. Calling it with no arguments leaves the array unchanged and returns its current length. JavaScript arrays can contain mixed types, meaning a single call may append numbers, strings, objects, or other arrays.
Several methods are easy to confuse with `push()`. `pop()` removes an item from the end, `unshift()` adds items to the beginning, and `shift()` removes one from the beginning. `concat()` usually creates and returns a new combined array without changing the original array.