We live in a world where information and data are very valuable. After all, this is the age where digital currencies have been created online to solve some real-world issues. Data is more than just random files that we access, alter and delete.It would stand to reason that these files and this information should be protected. This is where encryption and decryption come into play

What are encryption and decryption?

In simple terms, encryption is the process of translating plain text data (plaintext or information that we can all see and understand) into something that appears to be random and meaningless (ciphertext). Decryption is the process of converting ciphertext back to plaintext.

It encodes a message or information in such a way that only authorized parties can access it and those who are not authorized cannot. This is done using an algorithm to transform information to make it unreadable for unauthorized users.

Why is it such a big deal?

These processes effectively protect all sensitive information and prevent unauthorised access to your data, which can be from emails to WhatsApp messages and bank details, keeping communication secure between the parties involved.

What is PGP and what does it have to do with this?

To help with managing all the complicated issues around encryption and decryption, there are tools that people can install on their devices. One tried and popular solution is called PGP. PGP is an encryption program that provides cryptographic privacy and authentication for data. PGP is used for signing, encrypting, and decrypting texts, e-mails, files, directories, and whole disk partitions and to increase the security of e-mail communications. Some important points to remember about PGP are

  • PGP stands for Pretty Good Privacy.
  • It is a free encryption software solution.
  • It is a way to encrypt messages online.
  • You can encrypt and decrypt various types of files, texts, emails, etc.
  • It was invented in 1991

Here is how it works

I’m going to make use of an example to illustrate how it works

So, let’s say we have 2 people, Fatsani & Dennis. Both guys are on their computers. Fatsani wants to send a private message to Dennis, however, he has to send it via the internet & Fatsani knows who is on the internet – bad guys like Trevor (the Hacker).

So how would Fatsani send the message to Dennis without anyone to see it on the internet & understand it?

The answer is simple………

Fatsani and Dennis will both install PGP on their laptops.


  • Dennis will create a public and private key
  • He sends the public key to Fatsani (then he keeps the private key safe)


  • He encrypts the message using Dennis’ public key and sends the message to Dennis.


  • He decrypts the message using his own private key.


If Dennis wants to send a private message to Fatsani, Fatsani creates a private and public key and give Dennis his public key and then send the message.

Installation Process

Visit: https://gpgtools.org and download the GPG Suite.

Download complete!!!!!

Open the DMG file it will load. It will take you to this screen

ecryption and decryption, email security

Select install. It will take you to the following installer:-

encryption and decryption, email security

Click continue until it requires a password to finish the installation, input your Mac password and it will finish the installation process. Once it’s done, you’re all set.

The next step is to create a public & private key for your email that you want to send and receive the encrypted messages with.

Here is a video showing how you go about it including how to back-up the keys.

What are public & private keys

In any discussion on security, encryption and decryption the terms public key and private key often get brought up.These are two codes that ensure that a file that’s encrypted by one user is accessed only by the sender and the intended recipient.

Public key

This is created in public key encryption cryptography that uses asymmetric-key encryption algorithms. Public keys are used to convert a message into an unreadable format. It is made available to everyone via a publicly accessible repository or directory.

Private key

This is the secret key. It is a tiny bit of code that is paired with a public key to set off algorithms for text encryption and decryption.

The Public and Private key pair comprise of two uniquely related cryptographic keys (basically long random numbers). Below is an example of a Public Key:

3048 0241 00C9 18FA CF8D EB2D EFD5 FD37 89B9 E069 EA97 FC20 5E35 F577 EE31 C4FB C6E4 4811 7D86 BC8F BAFA 362F 922B F01B 2F40 C744 2654 C0DD 2881 D673 CA2B 4003 C266 E2CD CB02 0301 0001

The Public Key is what its name suggests – Public. It is made available to everyone via a publicly accessible directory. On the other hand, the Private Key must remain confidential to its respective owner.

Because the key pair is mathematically related, whatever is encrypted with a Public Key may only be decrypted by its corresponding Private Key and vice versa.