Fix wording

src/exercise/02.md

@@ -10,8 +10,8 @@ Elaborate on your learnings here in `src/exercise/02.md`
 
 Memoization: a performance optimization technique which eliminates the need to
 recompute a value for a given input by storing the original computation and
-returning that stored value when the same input is provided. Caching is a form
-of memoization. Here's a simple implementation of memoization:
+returning that stored value when the same input is provided. Memoization is a form
+of caching. Here's a simple implementation of memoization:
 
 ```typescript
 const values = {}