fixes

1-js/06-advanced-functions/08-settimeout-setinterval/article.md

@@ -387,9 +387,9 @@ For server-side JavaScript, that limitation does not exist, and there exist othe
 
 ### Allowing the browser to render
 
-Another benefit for in-browser scripts is that they can show a progress bar or something to the user. That's because the browser usually does all "repainting" after the script is complete.
+Another benefit of splitting heavy tasks for browser scripts is that we can show a progress bar or something to the user.
 
-So if we do a single huge function then even if it changes something, the changes are not reflected in the document till it finishes.
+Usually the browser does all "repainting" after the currently running code is complete. So if we do a single huge function that changes many elements, the changes are not painted out till it finishes.
 
 Here's the demo:
 ```html run
@@ -402,7 +402,7 @@ Here's the demo:
     for (let j = 0; j < 1e6; j++) {
       i++;
       // put the current i into the <div>
-      // (we'll talk more about innerHTML in the specific chapter, should be obvious here)
+      // (we'll talk about innerHTML in the specific chapter, it just writes into element here)
       progress.innerHTML = i;
     }
   }
@@ -446,9 +446,9 @@ Now the `<div>` shows increasing values of `i`.
 - Methods `setInterval(func, delay, ...args)` and `setTimeout(func, delay, ...args)` allow to run the `func` regularly/once after `delay` milliseconds.
 - To cancel the execution, we should call `clearInterval/clearTimeout` with the value returned by `setInterval/setTimeout`.
 - Nested `setTimeout` calls is a more flexible alternative to `setInterval`. Also they can guarantee the minimal time *between* the executions.
-- Zero-timeout scheduling `setTimeout(...,0)` is used to schedule the call "as soon as possible, but after the current code is complete".
+- Zero-timeout scheduling `setTimeout(func, 0)` (the same as `setTimeout(func)`) is used to schedule the call "as soon as possible, but after the current code is complete".
 
-Some use cases of `setTimeout(...,0)`:
+Some use cases of `setTimeout(func)`:
 - To split CPU-hungry tasks into pieces, so that the script doesn't "hang"
 - To let the browser do something else while the process is going on (paint the progress bar).
 

6-data-storage/02-localstorage/article.md

@@ -7,7 +7,7 @@ What's interesting about them is that the data survives a page refresh (for `ses
 We already have cookies. Why additional objects?
 
 - Unlike cookies, web storage objects are not sent to server with each request. Because of that, we can store much more. Most browsers allow at least 2 megabytes of data (or more) and have settings to configure that.
-- The server can't manipulate storage objects via HTTP headers, everything's done in JavaScript.
+- Also unlike cookies, the server can't manipulate storage objects via HTTP headers. Everything's done in JavaScript.
 - The storage is bound to the origin (domain/protocol/port triplet). That is, different protocols or subdomains infer different storage objects, they can't access data from each other.
 
 Both storage objects provide same methods and properties:
@@ -19,6 +19,8 @@ Both storage objects provide same methods and properties:
 - `key(index)` -- get the key on a given position.
 - `length` -- the number of stored items.
 
+As you can see, it's like a `Map` colection (`setItem/getItem/removeItem`), but also keeps elements order and allows to access by index with `key(index)`.
+
 Let's see how it works.
 
 ## localStorage demo
@@ -71,11 +73,11 @@ That's allowed for historical reasons, and mostly works, but generally not recom
 
 ## Looping over keys
 
-Methods provide get/set/remove functionality. But how to get all the keys?
+As we've seen, the methods provide get/set/remove functionality. But how to get all saved values or keys?
 
 Unfortunately, storage objects are not iterable.
 
-One way is to use "array-like" iteration:
+One way is to loop over them as over an array:
 
 ```js run
 for(let i=0; i<localStorage.length; i++) {
@@ -84,9 +86,9 @@ for(let i=0; i<localStorage.length; i++) {
 }
 ```
 
-Another way is to use object-specific `for key in localStorage` loop.
+Another way is to use `for key in localStorage` loop, just as we do with regular objects.
 
-That iterates over keys, but also outputs few built-in fields that we don't need:
+It iterates over keys, but also outputs few built-in fields that we don't need:
 
 ```js run
 // bad try