In general, it is not illegal to send song files on the internet if:
- You have the copyright or permission to share those files.
- You are sharing the files for non-commercial purposes, such as personal enjoyment or educational use.
The laws related to copyright can vary depending on the country or jurisdiction in which you are located, so it's important to familiarize yourself with the local copyright laws to ensure you are not violating any restrictions.
Also, individual platforms and services may have specific terms and conditions regarding the sharing of copyrighted material. For example, some platforms may prohibit the sharing of copyrighted music files, while others may allow it under certain circumstances, such as for promotional or educational purposes.
To be on the safe side, it's always a good idea to refer to the terms of service of the platform you are using to determine what is permitted and what is not regarding the sharing of music files.