There are two styles of public key, both with Base64 between the boundaries:<p><pre><code> -----BEGIN RSA PUBLIC KEY-----
-----END RSA PUBLIC KEY-----
and
-----BEGIN PUBLIC KEY-----
-----END PUBLIC KEY-----
</code></pre>
The top answer gives a stellar explanation of internals in response to OP asking how to convert between them.<p>For the former (older) format, there is this overview in the middle of the post:<p>> [This is an] PEM DER ASN.1 PKCS#1 RSA Public key<p>> - PEM: synonym for base64<p>> - DER: a flavor of ASN.1 encoding<p>> - ASN.1: the binary encoding scheme used<p>> - PKCS#1: The formal specification that dictates representing a public key as structure that consists of modulus followed by an exponent<p>> - RSA public key: the public key algorithm being used<p>Trivial!<p>I really appreciated the explanation of all these terms in one place, even if I question that PEM really just means Base64 it is likely a useful simplification.