Encryption is the process of encoding files in a manner that only authorized individuals can access them. Encryption does not, in itself, prevent interception, but it denies the file content to the interceptor. In an encryption scheme, the intended files, referred to as plaintext, are encrypted using an encryption algorithm, generating ciphertext that can only be read if decrypted.
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Linux distributions provide a few standard encryption/decryption tools that can prove handy at times. In this article, we have covered three such tools with proper standard examples, which will help you encrypt, decrypt, and password-protect your files.

This guide is tested on the Ubuntu 22.04 OS template; However, it should work with our other Ubuntu and Debian templates.

The GnuPG (GNU Privacy Guard, often abbreviated as GPG) package is included by default in most of today’s Linux distributions. If it’s not installed, you can install it using apt or yum from the repository.

To install GnuPG:

Now you can encrypt a file using GPG. As soon as you run the gpg command with option -c (encryption only with symmetric cipher) it will create a file testfile.txt.gpg.

Note: Enter Paraphrase twice to encrypt the given file. You can just specify a different algorithm, optionally. To see all the encryption algorithms present, you may execute:

Output example:

Now, if you want to decrypt the above encrypted file, you may use the following command:

Note: You must provide the same password you provided during encryption to decrypt when prompted.
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More information about GNU Privacy Guard on the official site:

​https://www.gnupg.org

It is one of the most famous archive formats, and it is so well-known that we generally refer to archive files as zip files in day-to-day communication. It uses the PKZIP stream cipher algorithm. By default, it is installed on our OS templates. However, to make sure it is installed, use:

Create an encrypted zip file using zip:

If you want to add more files to the zip archive:

Note. In the above example mypassword is our password used for encryption?

To decrypt the file:

You need to provide the same password you provided at encryption.
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By default, it is installed on our OS templates. However, to make sure it is installed, use:

To encrypt:

Explanation of each option used in the above command:
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enc encryption
​-aes-256-cbc the algorithm to be used;
-in full path of a file to be encrypted;
-out the full path where it will be decrypted.

To decrypt, use: