P E N C I L
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PEM & CERT 
  1. DER  or .CER or .CERT- binary
  2. PEM - base64
    ------ BEGIN CERTIFICATE---- .... ---END CERTIFICATE

To decode certficate:
  1. openssl x509 -in cert.pem -text -noout
  2. openssl x509 -in certificate.der -inform der -text -noout