The four basic principles of PGP encryption are:
- Private key is private. Don't expose it to other people. It is protected by password so don't tell the password to other people.
- Public key is public. You can send it to other people.
- The data which is encrypted by a public key can be decrypted to plaintext only by its private key.
- The data which is signed by a private key can be verified its integrity only by its public key
From the principle 3, when you want to encrypt a file to your partner you need his/her public key. And vice versa someone wants to encrypt a file to you; your public key is needed to encrypt the file by him/her. The most import thing for both to exchange data is to exchange each other's public key.
You need to create your key pair which is composed of a unique private key and public key before you can exchange your public key with other people. The first time you use the program you can generate your key pair by using the key management function.
Step 1: Generate a key Pair
Step 2: Export your public key and send it to someone who wants to communicate with you
Step 3: Import the public key which is from other people.
Step 4: Then you can encrypt a file with someone's public key and send the encrypted file to him/her. Or vice versa you can decrypt the encrypted file from other.
Next: using ezPGP Client GUI