diff --git a/src/day_5/notes.md b/src/day_5/notes.md
index ff6e1f5..04ebb66 100644
--- a/src/day_5/notes.md
+++ b/src/day_5/notes.md
@@ -67,12 +67,12 @@ Can be used for example with `grep`, `rg`, `find`, `fd`, `nvim`, etc.
 - `.`: Any character
 - `.*`: 0 or more characters
 - `.+`: 1 or more characters
-- `\w`: Word
-- `\w`: Not word
+- `\w`: Letter or number
+- `\W`: Not letter nor number
 - `\d`: Digit
-- `\d`: Not digit
+- `\D`: Not digit
 - `\s`: Whitespace
-- `\s`: Not whitespace
+- `\S`: Not whitespace
 
 ## More tools