Make introductory paragraph use simpler language.

index.html

@@ -317,9 +317,9 @@ <h2>Introduction</h2>
 Digital signatures, based on
 <a href="https://en.wikipedia.org/wiki/Public-key_cryptography">asymmetric
 cryptography</a>, can be used to make [=authentication=] and [=authorization=]
-schemes more difficult for adversaries to compromise. However,
-one shortcoming of digital signatures is the challenge in disseminating
-necessary information, such as public cryptographic keys and revocation information, to those who need
+schemes more difficult for adversaries to compromise. However, one shortcoming
+of digital signatures is the challenge in distributing necessary information,
+such as public cryptographic keys and revocation information, to those who need
 to verify the security of a digital signature.
       </p>