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# String.prototype.concat()

The **`concat()`** method concatenates
the string arguments to the calling string and returns a new string.

## Syntax

```js
concat(str1)
concat(str1, str2)
concat(str1, str2, /* …, */ strN)
```

### Parameters

- `strN`
  - : One or more strings to concatenate to `str`.

### Return value

A new string containing the combined text of the strings provided.

## Description

The `concat()` function concatenates the string arguments to the calling
string and returns a new string. Changes to the original string or the returned string
don't affect the other.

If the arguments are not of the type string, they are converted to string values before
concatenating.

The `concat()` method is very similar to the [addition/string concatenation operators](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Operators/Addition) (`+`, `+=`), except that `concat()` [coerces its arguments directly to strings](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String#string_coercion), while addition coerces its operands to primitives first. For more information, see the reference page for the [`+` operator](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Operators/Addition).
