Data security is undoubtedly one of the aspects that most concerns both private users and organizations. If you are a GNU / Linux user, Tomb may be the tool you were looking for. It’s a free and Open Source file encryption software that allows you to encrypt files containing sensitive information.
The way Tomb works is simple: users create a folder intended for encrypted storage within their file system and they only have to store the information they wish to protect there.
The content of the folder will be fully encrypted and can only be accessed using associated key files, which are also protected with a user-defined password. The system allows you to create as many encrypted folders (called "tombs") as necessary, as long as there is enough free space available on your device's hard drive.
To facilitate the use of this software, there is a GUI container called gtomb, especially useful for users with little experience in the use of this type of programs.
To know more details as well as its installation procedure, see the original article here.