Added clarity to the list rendering section

Author: nknk39

src/content/learn/index.md

@@ -247,7 +247,7 @@ return (
 );
 ```
 
-Notice how `<li>` has a `key` attribute. For each item in a list, you should pass a string or a number that uniquely identifies that item among its siblings. Usually, a key should be coming from your data, such as a database ID. React uses your keys to know what happened if you later insert, delete, or reorder the items.
+Notice how `<li>` has a `key` attribute. React requires keys to distinguish each item from the others. For each item in a list, you should pass a string or a number that uniquely identifies that item among its siblings. Usually, a key should be coming from your data, such as a database ID. React uses your keys to know what happened if you later insert, delete, or reorder the items. The keys are specific to a particular list of items.
 
 <Sandpack>