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+Compatibility with standards and other software
+==================================================
+
+Python-RSA implements encryption and signatures according to PKCS#1
+version 1.5. This makes it compatible with the OpenSSL RSA module.
+
+Keys are stored in PEM or DER format according to PKCS#1 v1.5. Private
+keys are compatible with OpenSSL. However, OpenSSL uses X.509 for its
+public keys, which are not supported.
+
+:Encryption:
+    PKCS#1 v1.5 with at least 8 bytes of random padding
+
+:Signatures:
+    PKCS#1 v1.5 using the following hash methods:
+    MD5, SHA-1, SHA-256, SHA-384, SHA-512
+
+:Private keys:
+    PKCS#1 v1.5 in PEM and DER format, ASN.1 type RSAPrivateKey
+
+:Public keys:
+    PKCS#1 v1.5 in PEM and DER format, ASN.1 type RSAPublicKey
+
+
+
+Public keys from OpenSSL
+--------------------------------------------------
+
+To get a Python-RSA-compatible public key from OpenSSL, you need the
+private key. Get the private key in PEM or DER format and run it
+through the ``pyrsa-priv2pub`` command::
+
+ 
+ Usage: pyrsa-priv2pub [options]
+ 
+ Reads a private key and outputs the corresponding public key. Both
+ private and public keys use the format described in PKCS#1 v1.5
+ 
+ Options:
+   -h, --help         show this help message and exit
+   --in=INFILENAME    Input filename. Reads from stdin if not specified
+   --out=OUTFILENAME  Output filename. Writes to stdout of not specified
+   --inform=INFORM    key format of input - default PEM
+   --outform=OUTFORM  key format of output - default PEM