PGP

OpenPGP is a standard. GnuPG is the most popular implementation, but there are others like Sequoia PGP.

Keyservers

Keyservers are synchronized via the SKS Keyserver Network.

GPG usage

gpg --clearsign message.txt

Export All Keys

# Export all public keys
gpg --export --armor > all-public-keys.asc

# Export all private/secret keys (including subkeys)
gpg --export-secret-keys --armor > all-private-keys.asc

Git GPG Signing

Using git config --global (or edit ~/.gitconfig)

set git config --global commit.gpgsign true or

[commit]
 gpgsign = true

commit.gpgsign is actually more useful if you want to turn off signing in a repository, git config commit.gpgsign false.

you can also set

same for user.signingkey <KEY_ID>

gpg.format <openpgp/ssh/x509>