diff --git a/book/source/04-certificates.md b/book/source/04-certificates.md
index d1f435c..7b0b456 100644
--- a/book/source/04-certificates.md
+++ b/book/source/04-certificates.md
@@ -165,9 +165,9 @@ Heiko, please clarify what the value is of this proposal or remove it.
 ```
 
 (primary_user_id)=
-### Implimations of the Primary User ID
+### Implications of the Primary User ID
 
-Within a certificate, a specific User ID is desginated as the [Primary User ID](https://www.ietf.org/archive/id/draft-ietf-openpgp-crypto-refresh-10.html#name-primary-user-id).
+Within a certificate, a specific User ID is designated as the [Primary User ID](https://www.ietf.org/archive/id/draft-ietf-openpgp-crypto-refresh-10.html#name-primary-user-id).
 
 Each User ID carries associated preference settings, such as preferred encryption algorithms, which is detailed in {numref}`zooming_in_user_id`). The preferences associated with the Primary User ID take precedence by default.