diff --git a/docs/hazmat/backends/openssl.rst b/docs/hazmat/backends/openssl.rst
index 791aab3..6a5ae6f 100644
--- a/docs/hazmat/backends/openssl.rst
+++ b/docs/hazmat/backends/openssl.rst
@@ -40,6 +40,12 @@
         Activates the OS random engine. This will effectively disable OpenSSL's
         default CSPRNG.
 
+    .. method:: osrandom_engine_implementation()
+
+        .. versionadded:: 1.7
+
+        Returns the implementation of OS random engine.
+
     .. method:: activate_builtin_random()
 
         This will activate the default OpenSSL CSPRNG.
@@ -81,6 +87,21 @@
 Linux uses its own PRNG design. ``/dev/urandom`` is a non-blocking source
 seeded from the same pool as ``/dev/random``.
 
++------------------------------------------+------------------------------+
+| Windows                                  | ``CryptGenRandom()``         |
++------------------------------------------+------------------------------+
+| Linux >= 3.4.17 with working             | ``getrandom(GRND_NONBLOCK)`` |
+| ``SYS_getrandom`` syscall                |                              |
++------------------------------------------+------------------------------+
+| OpenBSD >= 5.6                           | ``getentropy()``             |
++------------------------------------------+------------------------------+
+| BSD family (including macOS 10.12+) with | ``getentropy()``             |
+| ``SYS_getentropy`` in ``sys/syscall.h``  |                              |
++------------------------------------------+------------------------------+
+| fallback                                 | ``/dev/urandom`` with        |
+|                                          | cached file descriptor       |
++------------------------------------------+------------------------------+
+
 
 .. _`OpenSSL`: https://www.openssl.org/
 .. _`initializing the RNG`: https://en.wikipedia.org/wiki/OpenSSL#Predictable_private_keys_.28Debian-specific.29
diff --git a/docs/spelling_wordlist.txt b/docs/spelling_wordlist.txt
index 186b7ee..d57c4d2 100644
--- a/docs/spelling_wordlist.txt
+++ b/docs/spelling_wordlist.txt
@@ -33,6 +33,7 @@
 El
 Encodings
 endian
+fallback
 Fernet
 fernet
 FIPS
@@ -53,12 +54,14 @@
 multi
 namespace
 namespaces
+macOS
 naïve
 Nonces
 nonces
 online
 paddings
 Parallelization
+personalization
 pickleable
 plaintext
 pre
@@ -75,6 +78,7 @@
 Serializers
 SHA
 Solaris
+syscall
 Tanja
 testability
 tunable