diff --git a/28.md b/28.md
index 73c76b2b..6b240ef3 100644
--- a/28.md
+++ b/28.md
@@ -52,10 +52,17 @@ Clients MAY add additional metadata fields.
 
 Clients SHOULD use [NIP-10](10.md) marked "e" tags to recommend a relay.
 
+It is also possible to set the category name using the "t" tag. This category name can be searched and filtered.
+
 ```jsonc
 {
   "content": "{\"name\": \"Updated Demo Channel\", \"about\": \"Updating a test channel.\", \"picture\": \"https://placekitten.com/201/201\", \"relays\": [\"wss://nos.lol\", \"wss://nostr.mom\"]}",
-  "tags": [["e", <channel_create_event_id>, <relay-url>]],
+  "tags": [
+    ["e", <channel_create_event_id>, <relay-url>, "root"],
+    ["t", <category_name-1>],
+    ["t", <category_name-2>],
+    ["t", <category_name-3>],
+  ],
   // other fields...
 }
 ```