javascript-tutorial · javascript-translate-bot · Apr 21, 2019 · Apr 21, 2019 · Apr 21, 2019 · Apr 21, 2019
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diff --git a/1-js/01-getting-started/1-intro/article.md b/1-js/01-getting-started/1-intro/article.md
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 # JavaScript 简介
 
+<<<<<<< HEAD
 我们一起来聊一下 JavaScript，用它能做什么，它有哪些特性，以及一些跟它配合使用的技术。
+=======
+Let's see what's so special about JavaScript, what we can achieve with it, and which other technologies play well with it.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 ## 什么是 JavaScript？
 
+<<<<<<< HEAD
 **JavaScript** 最初的目的是为了“**赋予网页生命**”。
 
 这种编程语言我们称之为**脚本**。它们可以写在 HTML 中，在页面加载的时候会自动执行。
@@ -31,23 +36,64 @@ JavaScript 在刚诞生的时候，它的名字叫 “LiveScript”。但是因
 上面这些很容易记忆，因为经常出现在网上关于开发的文章中。我们也会这样用。例如：某个新的功能，如果 JavaScript 引擎 V8 是支持的，那么我们可以认为这个功能在 Chrome 和 Opera 中可以正常运行。
 
 ```smart header="引擎是如何工作的？"
+=======
+*JavaScript* was initially created to *"make web pages alive"*.
+
+The programs in this language are called *scripts*. They can be written right in a web page's HTML and run automatically as the page loads.
+
+Scripts are provided and executed as plain text. They don't need special preparation or compilation to run.
+
+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 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.
+```
+
+Today, JavaScript can execute not only 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 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" 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.
+
+```smart header="How do engines work?"
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 引擎很复杂，但是基本原理很简单。
 
 1. 引擎（通常嵌入在浏览器中）读取（“解析”）脚本。
 2. 然后将脚本转化（“编译”）为机器语言。
 3. 然后就可以在机器上飞速的运行。
 
+<<<<<<< HEAD
 引擎会对流程中的每个阶段都进行优化。它甚至可以在运行时监视编译的脚本，分析数据流并根据这些对机器代码应用优化。最后，脚本会执行地非常快。
+=======
+The engine applies optimizations at each step of the process. It even watches the compiled script as it runs, analyzes the data that flows through it, and applies optimizations to the machine code based on that knowledge. When it's done, scripts run quite fast.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 ```
 
 ## 浏览器中的 JavaScript 能做什么 ?
 
+<<<<<<< HEAD
 现代的 JavaScript 是一种“安全”语言。它不提供对内存或 CPU 的底层访问，因为它最初是为浏览器创建的，不需要这些功能。
 
 JavaScript 的能力依赖于它执行的环境。例如：[Node.js](https://wikipedia.org/wiki/Node.js) 允许 JavaScript 读写任意文件、执行网络请求等。
 
 浏览器中的 JavaScript 可以完成所有和网页相关的操作、处理用户和 Web 服务器之间的交互。
+=======
+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.
+
+JavaScript's capabilities greatly depend on the environment it's running in. 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.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 例如，浏览器中的 JavaScript 可以完成下面这些事：
 
@@ -61,7 +107,11 @@ JavaScript 的能力依赖于它执行的环境。例如：[Node.js](https://wik
 
 为了用户的（信息）安全，在浏览器中的 JavaScript 的能力是有限的。这样主要是为了阻止邪恶的网站获得或修改用户的私人数据。
 
+<<<<<<< HEAD
 这些限制的例子有：
+=======
+Examples of such restrictions include:
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 * 网页中的 JavaScript 不能读、写、复制及执行用户磁盘上的文件或程序。它没有直接访问操作系统的功能。
 
@@ -70,6 +120,7 @@ JavaScript 的能力依赖于它执行的环境。例如：[Node.js](https://wik
   JavaScript 有很多方式和设备的照相机/麦克风交互，但是这些都需要提前获得用户的授权许可。所以，JavaScript 并不会偷偷地通过你的摄像头观察你，更不会把你的信息发送到[美国国家安全局](https://en.wikipedia.org/wiki/National_Security_Agency)。
 - 不同的浏览器标签页之间基本彼此不相关。有时候，也会有一些关系。例如，通过 JavaScript 打开另外一个新的标签页。但即使在这种情况下，如果两个标签页打开的不是同一个网站（域名、协议或者端口任一不相同的网站），他们都不能够相互通信。
 
+<<<<<<< HEAD
   这就是“同源策略”。为了解决不同标签页交互的问题，两个同源的网站必须**都**包含一些特殊的 JavaScript 代码，才能够实现数据交换。
 
   这个限制也是为了用户的信息安全。例如，用户打开的 `http://anysite.com` 网页的 JavaScript 不能访问 `http://gmail.com`（另外一个标签页打开的网页）也不能从那里窃取信息。
@@ -78,22 +129,45 @@ JavaScript 的能力依赖于它执行的环境。例如：[Node.js](https://wik
 ![](limitations.png)
 
 浏览器环境外的 JavaScript 一般没有这些限制。例如服务端的 JavaScript 就没有这些限制。现代浏览器还允许通过 JavaScript 来安装浏览器插件或扩展，当然这也是在用户授权的前提下。
+=======
+    This is called the "Same Origin Policy". To work around that, *both pages* must agree for data exchange and contain a special JavaScript code that handles it. We'll cover that in the tutorial.
+
+    This limitation is, again, for the user's safety. A page from `http://anysite.com` which a user has opened must not be able to access another browser tab with the URL `http://gmail.com` and steal information from there.
+- JavaScript can easily communicate over the net to the server where the current page came from. But its ability to receive data from other sites/domains is crippled. Though possible, it requires explicit agreement (expressed in HTTP headers) from the remote side. Once again, that's a safety limitation.
+
+![](limitations.png)
+
+Such limits do not exist if JavaScript is used outside of the browser, for example on a server. Modern browsers also allow plugin/extensions which may ask for extended permissions.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 ## JavaScript 为什么与众不同？
 
 至少有 **3** 件事值得一提：
 
 ```compare
+<<<<<<< HEAD
 + 和 HTML/CSS 完全的集成。
 + 使用简单的工具完成简单的任务。
 + 被所有的主流浏览器支持，并且默认开启。
+=======
++ Full integration with HTML/CSS.
++ Simple things are done simply.
++ Support by all major browsers and enabled by default.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 ```
+JavaScript is the only browser technology that combines these three things.
 
+<<<<<<< HEAD
 满足这三条的浏览器技术也只有 JavaScript 了。
 
 这就是为什么 JavaScript 与众不同！这也是为什么它是创建浏览器界面的最普遍的工具。
 
 当然，学习一项新技术的时候，最好先看一下它的前景。所以，接下来我们继续讨论包括新语言和浏览器功能在内的现代趋势。
+=======
+That's what makes JavaScript unique. That's why it's the most widespread tool for creating browser interfaces.
+
+While planning to learn a new technology, it's beneficial to check its perspectives. So let's move on to the modern trends affecting it,  including new languages and browser abilities.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 
 ## 比 JavaScript “好” 的语言
@@ -104,18 +178,36 @@ JavaScript 的能力依赖于它执行的环境。例如：[Node.js](https://wik
 
 所以，最近出现了很多不同的语言，这些语言在浏览器中执行之前，都会被**编译**（转化）成 JavaScript。
 
+<<<<<<< HEAD
 现代化的工具使得编译速度非常快速和透明，实际上允许开发人员使用另一种语言编写代码并将其自动转换为 JavaScript。
+=======
+Modern tools make the transpilation very fast and transparent, actually allowing developers to code in another language and auto-converting it "under the hood".
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 这些语言的例子有：
 
+<<<<<<< HEAD
 - [CoffeeScript](http://coffeescript.org/) 是 JavaScript 的语法糖，它语法简短，明确简洁。通常使用 Ruby 的人喜欢用。
 - [TypeScript](http://www.typescriptlang.org/) 将注意力集中在增加严格的数据类型。这样就能简化开发，也能用于开发复杂的系统。TypeScript 是微软开发的。
 - [Dart](https://www.dartlang.org/) 是一门独立的语言。它拥有自己的引擎用于在非浏览器环境中运行（如：在手机应用中运行）。最开始是 Google 提供的用于替代 JavaScript 的，但是现在，它和其他上述的语言一样，浏览器也要求它被编译成 JavaScript 。
 
 当然，还有更多其他的语言。即使我们在使用这些语言，我们也需要知道 JavaScript。因为学习 JavaScript 可以让我们真正明白我们自己在做什么。
+=======
+- [CoffeeScript](http://coffeescript.org/) is a "syntactic sugar" for JavaScript. It introduces shorter syntax, allowing us to write clearer and more precise code. Usually, Ruby devs like it.
+- [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 these languages, we should also know JavaScript to really understand what we're doing.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 ## 总结
 
+<<<<<<< HEAD
 - JavaScript 最开始是为浏览器设计的一门语言，但是现在也可以在其它的环境中运行。
 - 现在，JavaScript 是一门在浏览器中使用最广、并且能够很好集成 HTML/CSS 的语言。
 - 有很多其他的语言可以编译成 JavaScript，这些语言还提供更多的功能。最好要了解一下这些语言，至少需要在掌握 JavaScript 之后简单地看一下。
+=======
+- JavaScript was initially created as a browser-only language, but is now used in many other environments as well.
+- Today, JavaScript has a unique position as the most widely-adopted browser language with full integration with HTML/CSS.
+- There are many languages that get "transpiled" to JavaScript and provide certain features. It is recommended to take a look at them, at least briefly, after mastering JavaScript.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
diff --git a/1-js/01-getting-started/1-intro/limitations.png b/1-js/01-getting-started/1-intro/limitations.png
diff --git a/1-js/01-getting-started/1-intro/limitations@2x.png b/1-js/01-getting-started/1-intro/limitations@2x.png
diff --git a/1-js/01-getting-started/2-code-editors/article.md b/1-js/01-getting-started/2-code-editors/article.md
@@ -2,6 +2,7 @@
 
 程序员接触时间最长的就是代码编辑器（后面简称编辑器）。
 
+<<<<<<< HEAD
 编辑器主要分两种：IDE（集成开发环境）和轻量编辑器。很多人喜欢这两种各选一个。
 
 ## IDE
@@ -19,38 +20,83 @@ IDE 加载项目（通常包含多个文件），并且允许在不同文件之
 除了 Visual Studio，以上这些 IDE 都是跨平台的。Visual Studio 无法在 Linux 上使用。
 
 大多数 IDE 是收费的，但是他们都可以试用。这些费用对于一个合格的程序员的薪水来说，肯定算不了什么，所以去选一个对你来说最好的吧。
+=======
+There are two main types of code editors: IDEs and lightweight editors. Many people use one tool of each type.
+
+## IDE
+
+The term [IDE](https://en.wikipedia.org/wiki/Integrated_development_environment) (Integrated Development Environment) refers to a powerful editor with many features that usually operates on a "whole project." As the name suggests, it's not just an editor, but a full-scale "development environment."
+
+An IDE loads the project (which can be many files), allows navigation between files, provides autocompletion based on the whole project (not just the open file), and integrates with a version management system (like [git](https://git-scm.com/)), a testing environment, and other "project-level" stuff.
+
+If you haven't selected an IDE yet, consider the following options:
+
+- [WebStorm](http://www.jetbrains.com/webstorm/) for frontend development. The same company offers other editors for other languages (paid).
+- [Netbeans](http://netbeans.org/) (free).
+
+All of these IDEs are cross-platform.
+
+For Windows, there's also "Visual Studio", not to be confused 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.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 ## 轻量编辑器
 
 “轻量编辑器”没有 IDE 那么功能强大，但是他们一般很快、优雅而且简单。
 
+<<<<<<< HEAD
 “轻量编辑器”主要用于立即打开编辑一个文件。
+=======
+They are mainly used to open and edit a file instantly.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 “轻量编辑器”和 IDE 有很大的区别。IDE 一般是项目中使用，就意味着一开始要加载很多数据，并且在使用的过程中会分析项目的结构和内容。如果我们只需要编辑一个文件，那么 “轻量编辑器” 会更快的帮我们打开文件。
 
 实际上，“轻量编辑器”一般都有各种各样的插件，这些插件可以做语法分析和补全代码。所以“轻量编辑器”和 IDE 也没有严格的界限。
 
 下面是一些流行的“轻量编辑器”：
 
+<<<<<<< HEAD
 - [Visual Studio Code](https://code.visualstudio.com/)（跨平台、免费）。
 - [Atom](https://atom.io/)（跨平台、免费）。
 - [Sublime Text](http://www.sublimetext.com)（跨平台、共享软件）。
 - [Notepad++](https://notepad-plus-plus.org/)（Windows、免费）。
 - [Vim](http://www.vim.org/) 和 [Emacs](https://www.gnu.org/software/emacs/) 很棒，前提是如果你知道怎么用。
+=======
+- [Visual Studio Code](https://code.visualstudio.com/) (cross-platform, free) also has many IDE-like features.
+- [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.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 ## 我的最爱
 
 我个人喜好是同时拥有项目级别的 IDE 和轻量级的编辑器，以便快速轻松地进行文件编辑。
 
 我使用的编辑器：
 
+<<<<<<< HEAD
 - 使用 [WebStorm](http://www.jetbrains.com/webstorm/) 写 JavaScript，如果项目涉及其他语言我切换到上面列出的其他 Jetbrains 产品之一。
 - 轻量编辑器 —— [Sublime Text](http://www.sublimetext.com) 或 [Atom](https://atom.io/)。
+=======
+- As an IDE for JS -- [WebStorm](http://www.jetbrains.com/webstorm/) (I switch to one of the other JetBrains offerings when using other languages)
+- As a lightweight editor -- [Sublime Text](http://www.sublimetext.com) or [Atom](https://atom.io/).
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 ## 不要争吵
 
+<<<<<<< HEAD
 上面列表中的编辑器都是我或我的朋友（他们都是我认为很优秀的开发人员）已经使用了很长时间并且很满意的。
+=======
+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.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb
 
 世上还有很多其他的很好的编辑器，你们可以选择一个自己最喜欢的。
 
+<<<<<<< HEAD
 选择编辑器就像选择其他工具一样。要看你的项目，以及个人的习惯、喜好。
+=======
+The choice of an editor, like any other tool, is individual and depends on your projects, habits, and personal preferences.
+>>>>>>> a0266c574c0ab8a0834dd38ed65e7e4ee27f9cdb