PKCS #1 private key syntax vs PKCS #8

Recently I've been looking at a RSA private key embedded in a configuration file. Things weren't working as expected so I started looking at the key more closely. The string I had was a base64 encoded ASN structure. I came across 2 formats of these structures and . Luckily OpenSSL seemed to have no problem reading either so this wasn't actually an issue for me, just something I hadn't appreciated.