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@@ -0,0 +1 @@
+* text=auto eol=lf

1-js/01-getting-started/1-intro/article.md

@@ -1,32 +1,32 @@
 # An Introduction to JavaScript
 
-Let's see what's so special about JavaScript, what we can achieve with it and which other technologies play well with it.
+Let's see what's so special about JavaScript, what we can achieve with it, and which other technologies play well with it.
 
 ## What is JavaScript?
 
-*JavaScript* was initially created to *"make webpages alive"*.
+*JavaScript* was initially created to *"make web pages alive"*.
 
-The programs in this language are called *scripts*. They can be written right in the HTML and execute automatically as the page loads.
+The programs in this language are called *scripts*. They can be written right in the HTML and executed automatically as the page loads.
 
 Scripts are provided and executed as a plain text. They don't need a special preparation or a compilation to run.
 
-In this aspect, JavaScript is very different from another language called [Java](http://en.wikipedia.org/wiki/Java).
+In this aspect, JavaScript is very different from another language called [Java](https://en.wikipedia.org/wiki/Java_(programming_language)).
 
 ```smart header="Why <u>Java</u>Script?"
 When JavaScript was created, it initially had another name: "LiveScript". But Java language was very popular at that time, so it was decided that positioning a new language as a "younger brother" of Java would help.
 
 But as it evolved, JavaScript became a fully independent language, with its own specification called [ECMAScript](http://en.wikipedia.org/wiki/ECMAScript), and now it has no relation to Java at all.
 ```
 
-At present, JavaScript can execute not only in the browser, but also on the server, or actually on any device where there exists a special program called [the JavaScript engine](https://en.wikipedia.org/wiki/JavaScript_engine).
+At present, JavaScript can not only execute in the browser, but also on the server, or actually on any device that has a special program called [the JavaScript engine](https://en.wikipedia.org/wiki/JavaScript_engine).
 
-The browser has an embedded engine, sometimes it's also called a "JavaScript virtual machine".
+The browser has an embedded engine, sometimes called a "JavaScript virtual machine".
 
 Different engines have different "codenames", for example:
 
 - [V8](https://en.wikipedia.org/wiki/V8_(JavaScript_engine)) -- in Chrome and Opera.
 - [SpiderMonkey](https://en.wikipedia.org/wiki/SpiderMonkey) -- in Firefox.
-- ...There are other codenames like "Trident", "Chakra" for different versions of IE, "ChakraCore" for Microsoft Edge, "Nitro" and "SquirrelFish" for Safari etc.
+- ...There are other codenames like "Trident" and "Chakra" for different versions of IE, "ChakraCore" for Microsoft Edge, "Nitro" and "SquirrelFish" for Safari, etc.
 
 The terms above are good to remember, because they are used in developer articles on the internet. We'll use them too. For instance, if "a feature X is supported by V8", then it probably works in Chrome and Opera.
 
@@ -45,9 +45,9 @@ The engine applies optimizations on every stage of the process. It even watches
 
 The modern JavaScript is a "safe" programming language. It does not provide low-level access to memory or CPU, because it was initially created for browsers which do not require it.
 
-The capabilities greatly depend on the environment that runs JavaScript. For instance, [Node.JS](https://wikipedia.org/wiki/Node.js) supports functions that allow JavaScript to read/write arbitrary files, perform network requests etc.
+The capabilities greatly depend on the environment that runs JavaScript. For instance, [Node.JS](https://wikipedia.org/wiki/Node.js) supports functions that allow JavaScript to read/write arbitrary files, perform network requests, etc.
 
-In-browser JavaScript can do everything related to webpage manipulation, interaction with the user and the webserver.
+In-browser JavaScript can do everything related to webpage manipulation, interaction with the user, and the webserver.
 
 For instance, in-browser JavaScript is able to:
 
@@ -85,7 +85,7 @@ There are at least *three* great things about JavaScript:
 
 ```compare
 + Full integration with HTML/CSS.
-+ Simple things done simply.
++ Simple things are done simply.
 + Supported by all major browsers and enabled by default.
 ```
 
@@ -104,15 +104,15 @@ That's to be expected, because projects and requirements are different for every
 
 So recently a plethora of new languages appeared, which are *transpiled* (converted) to JavaScript before they run in the browser.
 
-Modern tools make the transpilation very fast and transparent, actually allowing developers to code in another language and autoconverting it "under the hood".
+Modern tools make the transpilation very fast and transparent, actually allowing developers to code in another language and auto-converting it "under the hood".
 
 Examples of such languages:
 
 - [CoffeeScript](http://coffeescript.org/) is a "syntactic sugar" for JavaScript, it introduces shorter syntax, allowing to write more precise and clear code. Usually Ruby devs like it.
-- [TypeScript](http://www.typescriptlang.org/) is concentrated on adding "strict data typing", to simplify development and support of complex systems. It is developed by Microsoft.
+- [TypeScript](http://www.typescriptlang.org/) is concentrated on adding "strict data typing", to simplify the development and support of complex systems. It is developed by Microsoft.
 - [Dart](https://www.dartlang.org/) is a standalone language that has its own engine that runs in non-browser environments (like mobile apps). It was initially offered by Google as a replacement for JavaScript, but as of now, browsers require it to be transpiled to JavaScript just like the ones above.
 
-There are more. Of course even if we use one of those languages, we should also know JavaScript, to really understand what we're doing.
+There are more. Of course, even if we use one of those languages, we should also know JavaScript, to really understand what we're doing.
 
 ## Summary
 

1-js/01-getting-started/2-code-editors/article.md

@@ -6,25 +6,27 @@ There are two archetypes: IDE and lightweight editors. Many people feel comforta
 
 ## IDE
 
-The term [IDE](https://en.wikipedia.org/wiki/Integrated_development_environment) (Integrated Development Environment) means a powerful editor with many features that usually operates on a "whole project". As the name suggests, that's not just an editor, but a full-scale "development environment".
+The term [IDE](https://en.wikipedia.org/wiki/Integrated_development_environment) (Integrated Development Environment) means a powerful editor with many features that usually operates on a "whole project." As the name suggests, that's not just an editor, but a full-scale "development environment."
 
 An IDE loads the project (can be many files), allows navigation between files, provides autocompletion based on the whole project (not just the open file), integrates with a version management system (like [git](https://git-scm.com/)), a testing environment and other "project-level" stuff.
 
 If you haven't considered selecting an IDE yet, look at the following variants:
 
-- [WebStorm](http://www.jetbrains.com/webstorm/) for frontend development and other editors of the same company if you need additional languages.
-- Visual Studio is fine if you're a .NET developer, and a free version is available ([Visual Studio Community](https://www.visualstudio.com/vs/community/))
-- [Netbeans](http://netbeans.org/).
+- [WebStorm](http://www.jetbrains.com/webstorm/) for frontend development and other editors of the same company if you need additional languages (paid).
+- [Visual Studio Code](https://code.visualstudio.com/) (free).
+- [Netbeans](http://netbeans.org/) (paid).
 
-All of the IDEs except Visual Studio are available on Windows, MacOs and Linux. Visual Studio doesn't work on Linux.
+All of the IDEs are cross-platform.
 
-Most IDEs are paid, but have a trial period. Their cost is usually negligible compared to a qualified developer's salary, so just choose the best one for you.
+For Windows, there's also a "Visual Studio" editor, don't confuse it with "Visual Studio Code." "Visual Studio" is a paid and mighty Windows-only editor, well-suited for the .NET platform. A free version of it is called ([Visual Studio Community](https://www.visualstudio.com/vs/community/).
+
+Many IDEs are paid but have a trial period. Their cost is usually negligible compared to a qualified developer's salary, so just choose the best one for you.
 
 ## Lightweight editors
 
 "Lightweight editors" are not as powerful as IDEs, but they're fast, elegant and simple.
 
-They are mainly used to instantly open and edit a file.
+They are mainly used to open and edit a file instantly.
 
 The main difference between a "lightweight editor" and an "IDE" is that an IDE works on a project-level, so it loads much more data on start, analyzes the project structure if needed and so on. A lightweight editor is much faster if we need only one file.
 
@@ -36,20 +38,20 @@ The following options deserve your attention:
 - [Atom](https://atom.io/) (cross-platform, free).
 - [Sublime Text](http://www.sublimetext.com) (cross-platform, shareware).
 - [Notepad++](https://notepad-plus-plus.org/) (Windows, free).
-- [Vim](http://www.vim.org/) and [Emacs](https://www.gnu.org/software/emacs/) are also cool, if you know how to use them.
+- [Vim](http://www.vim.org/) and [Emacs](https://www.gnu.org/software/emacs/) are also cool if you know how to use them.
 
 ## My favorites
 
 The personal preference of the author is to have both an IDE for projects and a lightweight editor for quick and easy file editing.
 
 I'm using:
 
-- [WebStorm](http://www.jetbrains.com/webstorm/) for JS, and if there is one more language in the project, then I switch to one of the other Jetbrains offerings listed above.
+- [WebStorm](http://www.jetbrains.com/webstorm/) for JS, and if there is one more language in the project, then I switch to one of the other JetBrains offerings listed above.
 - As a lightweight editor -- [Sublime Text](http://www.sublimetext.com) or [Atom](https://atom.io/).
 
 ## Let's not argue
 
-The editors in the lists above are those that either I or my friends who I consider good developers have been using for a long time and are happy with.
+The editors in the lists above are those that either I or my friends whom I consider good developers have been using for a long time and are happy with.
 
 There are other great editors in our big world. Please choose the one you like the most.
 

1-js/01-getting-started/3-devtools/article.md

@@ -4,11 +4,11 @@ Code is prone to errors. You are quite likely to make errors... Oh, what am I ta
 
 But in the browser, a user doesn't see the errors by default. So, if something goes wrong in the script, we won't see what's broken and can't fix it.
 
-To see errors and get a lot of other useful information about scripts, browsers have embedded "developer tools".
+To see errors and get a lot of other useful information about scripts, "developer tools" have been embedded in browsers.
 
-Most often developers lean towards Chrome or Firefox for development, because those browsers have the best developer tools. Other browsers also provide developer tools, sometimes with special features, but are usually playing "catch-up" to Chrome or Firefox. So most people have a "favorite" browser and switch to others if a problem is browser-specific.
+Most often developers lean towards Chrome or Firefox for development because those browsers have the best developer tools. Other browsers also provide developer tools, sometimes with special features, but are usually playing "catch-up" to Chrome or Firefox. So most people have a "favorite" browser and switch to others if a problem is browser-specific.
 
-Developer tools are really powerful, there are many features. To start, we'll learn how to open them, look at errors and run JavaScript commands.
+Developer tools are potent; there are many features. To start, we'll learn how to open them, look at errors and run JavaScript commands.
 
 ## Google Chrome
 
@@ -24,21 +24,21 @@ It looks somewhat like this:
 
 ![chrome](chrome.png)
 
-The exact look of developer tools depends on your version of Chrome. It changes from time to time, but should be similar.
+The exact look of developer tools depends on your version of Chrome. It changes from time to time but should be similar.
 
-- Here we can see the red-colored error message. In this case the script contains an unknown "lalala" command.
+- Here we can see the red-colored error message. In this case, the script contains an unknown "lalala" command.
 - On the right, there is a clickable link to the source `bug.html:12` with the line number where the error has occurred.
 
-Below the error message there is a blue `>` symbol. It marks a "command line" where we can type JavaScript commands and press `key:Enter` to run them (`key:Shift+Enter` to input multi-line commands).
+Below the error message, there is a blue `>` symbol. It marks a "command line" where we can type JavaScript commands. Press `key:Enter` to run them (`key:Shift+Enter` to input multi-line commands).
 
-Now we can see errors and that's enough for the start. We'll be back to developer tools later and cover debugging more in-depth in the chapter <info:debugging-chrome>.
+Now we can see errors, and that's enough for a start. We'll be back to developer tools later and cover debugging more in-depth in the chapter <info:debugging-chrome>.
 
 
-## Firefox, Edge and others
+## Firefox, Edge, and others
 
 Most other browsers use `key:F12` to open developer tools.
 
-The look & feel of them is quite similar. Once you know how to use one of them (you can start with Chrome), you can easily switch to another.
+The look & feel of them is quite similar. Once you know how to use one of those tools (you can start with Chrome), you can easily switch to another.
 
 ## Safari
 
@@ -48,11 +48,11 @@ Open Preferences and go to "Advanced" pane. There's a checkbox at the bottom:
 
 ![safari](safari.png)
 
-Now `key:Cmd+Opt+C` can toggle the console. Also note that the new top menu item named "Develop" has appeared. It has many commands and options.
+Now `key:Cmd+Opt+C` can toggle the console. Also, note that the new top menu item named "Develop" has appeared. It has many commands and options.
 
 ## Summary
 
 - Developer tools allow us to see errors, run commands, examine variables and much more.
 - They can be opened with `key:F12` for most browsers under Windows. Chrome for Mac needs `key:Cmd+Opt+J`, Safari: `key:Cmd+Opt+C` (need to enable first).
 
-Now we have the environment ready. In the next section we'll get down to JavaScript.
+Now we have the environment ready. In the next section, we'll get down to JavaScript.

1-js/02-first-steps/01-hello-world/article.md

@@ -2,7 +2,7 @@
 
 The tutorial that you're reading is about core JavaScript, which is platform-independent. Further on, you will learn Node.JS and other platforms that use it.
 
-But, we need a working environment to run our scripts, and, just because this book is online, the browser is a good choice. We'll keep the amount of browser-specific commands (like `alert`) to a minimum, so that you don't spend time on them if you plan to concentrate on another environment like Node.JS. On the other hand, browser details are explained in detail in the [next part](/ui) of the tutorial.
+But, we need a working environment to run our scripts, and, just because this book is online, the browser is a good choice. We'll keep the amount of browser-specific commands (like `alert`) to a minimum so that you don't spend time on them if you plan to concentrate on another environment like Node.JS. On the other hand, browser details are explained in detail in the [next part](/ui) of the tutorial.
 
 So first, let's see how to attach a script to a webpage. For server-side environments, you can just execute it with a command like `"node my.js"` for Node.JS.
 
@@ -47,10 +47,10 @@ The `<script>` tag has a few attributes that are rarely used nowadays, but we ca
 
  The `type` attribute: <code>&lt;script <u>type</u>=...&gt;</code>
 
- : The old standard HTML4 required a script to have a type. Usually it was `type="text/javascript"`. It's not required any more. Also, the modern standard totally changed the meaning of this attribute. Now it can be used for Javascript modules. But that's an advanced topic, but we'll talk about modules later in another part of the tutorial. 
+ : The old standard HTML4 required a script to have a type. Usually it was `type="text/javascript"`. It's not required anymore. Also, the modern standard totally changed the meaning of this attribute. Now it can be used for Javascript modules. But that's an advanced topic; we'll talk about modules later in another part of the tutorial. 
 
  The `language` attribute: <code>&lt;script <u>language</u>=...&gt;</code>
-  : This attribute was meant to show the language of the script. As of now, this attribute makes no sense, the language is JavaScript by default. No need to use it.
+  : This attribute was meant to show the language of the script. This attribute no longer makes sense, because JavaScript is the default language. No need to use it.
 
 Comments before and after scripts.
 : In really ancient books and guides, one may find comments inside `<script>`, like this:
@@ -61,7 +61,7 @@ Comments before and after scripts.
     //--></script>
     ```
 
-    This trick isn't used in modern JavaScript. These comments were used to hide the JavaScript code from old browsers that didn't know about a `<script>` tag. Since browsers born in the last 15 years don't have this issue, this kind of comment can help you identify really old code.
+    This trick isn't used in modern JavaScript. These comments were used to hide the JavaScript code from old browsers that didn't know about a `<script>` tag. Since browsers released in the last 15 years don't have this issue, this kind of comment can help you identify really old code.
 
 
 ## External scripts
@@ -78,7 +78,7 @@ Here `/path/to/script.js` is an absolute path to the file with the script (from
 
 It is also possible to provide a path relative to the current page. For instance, `src="script.js"` would mean a file `"script.js"` in the current folder.
 
-We can give a full URL as well, for instance:
+We can give a full URL as well. For instance:
 
 ```html
 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/3.2.0/lodash.js"></script>
@@ -95,7 +95,7 @@ To attach several scripts, use multiple tags:
 ```smart
 As a rule, only the simplest scripts are put into HTML. More complex ones reside in separate files.
 
-The benefit of a separate file is that the browser will download it and then store in its [cache](https://en.wikipedia.org/wiki/Web_cache).
+The benefit of a separate file is that the browser will download it and then store it in its [cache](https://en.wikipedia.org/wiki/Web_cache).
 
 After this, other pages that want the same script will take it from the cache instead of downloading it. So the file is actually downloaded only once.