diff --git a/chapters/appendix-useful-distributions.md b/chapters/appendix-useful-distributions.md
index 8a96be5..987a509 100644
--- a/chapters/appendix-useful-distributions.md
+++ b/chapters/appendix-useful-distributions.md
@@ -1,7 +1,7 @@
 ---
 layout: chapter
 title: Appendix - Useful distribtuions
-description: A very brief sumary of some important distributions.
+description: A very brief summary of some important distributions.
 chapter_num: 21
 ---
 
@@ -76,4 +76,4 @@ var acat = function () {Categorical({
   })}
   
 sample(acat())
-~~~~
\ No newline at end of file
+~~~~