Update snippet descriptions

snippets/sum.md

@@ -3,7 +3,7 @@ title: sum
 tags: math,array,beginner
 ---
 
-Returns the sum of two or more numbers/arrays.
+Calculates the sum of two or more numbers/arrays.
 
 - Use `Array.prototype.reduce()` to add each value to an accumulator, initialized with a value of `0`.
 
@@ -14,4 +14,4 @@ const sum = (...arr) => [...arr].reduce((acc, val) => acc + val, 0);
 ```js
 sum(1, 2, 3, 4); // 10
 sum(...[1, 2, 3, 4]); // 10
-```
+```