> For the complete documentation index, see [llms.txt](https://trizen.gitbook.io/sidef-lang/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trizen.gitbook.io/sidef-lang/sidef_interpreter/interactive.md).

# Interactive mode

The interactive mode (a.k.a. REPL) is available by simply executing the `sidef` command, or by specifying the `-i` command-line switch.

```shell
$ sidef -i
Sidef 3.99, running on Linux, using Perl v5.34.0.
Type "help", "copyright" or "license" for more information.
>> n = 41
=> 41
>> n**2 + n - 1
=> 1721
>>
```