PGP or Pretty Good Privacy is an encryption method .. the public block is what is shared and the private key is what makes it readable. Found this explanation on .. drum roll, please .. kraken.com.
https://support.kraken.com/hc/en-us/articles/201648223-What-is-PGP-GPG-encryption-?msclkid=448e86653c56144ffefae742bbd76da6