Lowercase a.
diff --git a/docs/installation.rst b/docs/installation.rst
index 6867e96..a2bb4aa 100644
--- a/docs/installation.rst
+++ b/docs/installation.rst
@@ -136,7 +136,7 @@
 
     $ env DYLD_LIBRARY_PATH="$HOME/anaconda/lib" pip install cryptography
 
-And on Linux:
+and on Linux:
 
 .. code-block:: console