diff --git a/book/source/01-intro.md b/book/source/01-intro.md
index 8c65f77..2ddce83 100644
--- a/book/source/01-intro.md
+++ b/book/source/01-intro.md
@@ -17,8 +17,8 @@ OpenPGP is an open standard for cryptographic operations. It is a system based o
 
 With OpenPGP, you can:
 
-- [Encrypt](encryption_chapter) and [decrypt](decryption_chapter) messages
-- [Sign](signing_data) and [verify](verification_chapter) data
+- [Encrypt](encryption_chapter) and [decrypt](decryption_chapter) messages to achieve confidentiality
+- [Sign](signing_data) and [verify](verification_chapter) data to ensure authenticity
 - [Issue and validate certifications](component_signatures_chapter) about keys and identities, similar to the role of a Certificate Authority in validating identities.
 
 ## Who is the audience for this document?