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# ROT13 Decoding Username

***

Decode ROT13 obfuscated strings using the `rot13` command.

```bash
echo "wbxre" | rot13
```

This command decodes the input `wbxre` to `joker`. ROT13 is often used for basic obfuscation rather than strong encryption. Applying the transform a second time decodes the string back to its original form.

On Unix-like systems, the `tr` command can also be used to perform ROT13 substitution. The `tr` command is used for translating or deleting characters. To perform ROT13, you provide the original alphabet as the source set and the ROT13 shifted alphabet as the destination set.

```bash
echo "Hello World" | tr 'A-Za-z' 'N-ZA-Mn-za-m'
```

Applying the `tr` command with the same character sets to the output of a previous ROT13 transformation will decode it. For example, `echo "Uryyb Jbeyq" | tr 'A-Za-z' 'N-ZA-Mn-za-m'` will decode "Uryyb Jbeyq" back to "Hello World".

Another command-line method involves using Perl:

```bash
echo "Hello World" | perl -pe 'tr/a-zA-Z/n-za-mN-ZA-M/'
```

This Perl one-liner achieves the same ROT13 transformation by translating characters from the first set (`a-zA-Z`) to the second (`n-za-mN-ZA-M`).