javascript-tutorial · javascript-translate-bot · Sep 21, 2020 · Sep 22, 2020 · Sep 22, 2020 · Sep 22, 2020
diff --git a/1-js/01-getting-started/1-intro/article.md b/1-js/01-getting-started/1-intro/article.md
@@ -106,12 +106,20 @@
 
 ऐसी भाषाओं के उदाहरण:
 
+<<<<<<< HEAD
 - [CoffeeScript](http://coffeescript.org/) यह जावास्क्रिप्ट के लिए "सिंटैक्टिक शुगर" है। यह छोटे वाक्यविन्यास का परिचय देता है, जिससे हमें स्पष्ट और अधिक सटीक कोड लिखने की अनुमति मिलती है। आमतौर पर, Ruby (रूबी) डेवलपर इसे पसंद करते हैं।
 - [TypeScript](http://www.typescriptlang.org/) यह जटिल प्रणालियों के विकास और समर्थन को आसान बनाने के लिए "सख्त डेटा टाइपिंग" को जोड़ने पर केंद्रित है। यह Microsoft द्वारा विकसित किया गया है।
 - [Flow](http://flow.org/) यह डेटा टाइपिंग भी जोड़ता है, लेकिन एक अलग तरीके से। Facebook द्वारा विकसित।
 - [Dart](https://www.dartlang.org/) यह एक स्वतंत्र भाषा है जिसका अपना इंजन है जो गैर-ब्राउज़र वातावरण (जैसे मोबाइल ऐप) में चलता है, लेकिन इसे जावास्क्रिप्ट पर भी रूपांतरित किया जा सकता है। Google द्वारा विकसित किया गया।
 और भी कई हैं। बेशक, भले ही हम रूपांतरित भाषाओं में से एक का उपयोग करें, हमें यह भी जानना चाहिए कि हम वास्तव में क्या कर रहे हैं, यह समझने के लिए जावास्क्रिप्ट जानना महत्वपूर्ण है।
 - [Brython](https://brython.info/) यह जावास्क्रिप्ट के लिए एक पायथन ट्रांसपिलर है जो जावास्क्रिप्ट के बिना शुद्ध पायथन में एप्लिकेशन लिखने में सक्षम बनाता है।
+=======
+- [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.
+- [Flow](http://flow.org/) also adds data typing, but in a different way. Developed by Facebook.
+- [Dart](https://www.dartlang.org/) is a standalone language that has its own engine that runs in non-browser environments (like mobile apps), but also can be transpiled to JavaScript. Developed by Google.
+- [Brython](https://brython.info/) is a Python transpiler to JavaScript that enables the writing of applications in pure Python without JavaScript.
+>>>>>>> e1a3f634a47c119cf1ec7420c49fc0fc7172c0b5
 
 ## सारांश
 

diff --git a/1-js/01-getting-started/4-devtools/article.md b/1-js/01-getting-started/4-devtools/article.md
@@ -8,7 +8,11 @@
 
 अधिकांश डेवलपर विकास के लिए क्रोम या फ़ायरफ़ॉक्स की ओर झुकते हैं क्योंकि उन ब्राउज़र में सबसे अच्छा डेवलपर टूल होता है। अन्य ब्राउज़र भी डेवलपर उपकरण प्रदान करते हैं, कभी-कभी विशेष सुविधाओं के साथ, लेकिन आमतौर पर क्रोम या फ़ायरफ़ॉक्स के करीब नहीं होते हैं। इसलिए अधिकांश डेवलपर्स के पास "पसंदीदा" ब्राउज़र होता है और यदि कोई समस्या ब्राउज़र-विशिष्ट है तो ही दूसरों का उपयोग करता है।
 
+<<<<<<< HEAD
 डेवलपर उपकरण शक्तिशाली हैं; उनकी कई विशेषताएं हैं। शुरू करने के लिए, हम सीखेंगे कि उन्हें कैसे खोलें, त्रुटियों को देखें और जावास्क्रिप्ट कमांड चलाएं।
+=======
+Developer tools are potent, they have many features. To start, we'll learn how to open them, look at errors, and run JavaScript commands.
+>>>>>>> e1a3f634a47c119cf1ec7420c49fc0fc7172c0b5
 
 ## गूगल क्रोम (Google Chrome)
 

diff --git a/1-js/02-first-steps/01-hello-world/article.md b/1-js/02-first-steps/01-hello-world/article.md
@@ -10,7 +10,13 @@
 
 जावास्क्रिप्ट प्रोग्रामों को HTML दस्तावेज़ के किसी भी भाग में `<script>` टैग की सहायता से डाला जा सकता है।
 
+<<<<<<< HEAD
 उदाहरण के लिए:
+=======
+JavaScript programs can be inserted almost anywhere into an HTML document using the `<script>` tag.
+
+For instance:
+>>>>>>> e1a3f634a47c119cf1ec7420c49fc0fc7172c0b5
 
 ```html run height=100
 <!DOCTYPE HTML>

diff --git a/1-js/04-object-basics/01-object/article.md b/1-js/04-object-basics/01-object/article.md
@@ -92,30 +92,6 @@ let user = {
 ```
 That is called a "trailing" or "hanging" comma. Makes it easier to add/remove/move around properties, because all lines become alike.
 
-````smart header="Object with const can be changed"
-Please note: an object declared as `const` *can* be modified.
-
-For instance:
-
-```js run
-const user = {
-  name: "John"
-};
-
-*!*
-user.name = "Pete"; // (*)
-*/!*
-
-alert(user.name); // Pete
-```
-
-It might seem that the line `(*)` would cause an error, but no. The `const` fixes the value of `user`, but not its contents.
-
-The `const` would give an error only if we try to set `user=...` as a whole.
-
-There's another way to make constant object properties, we'll cover it later in the chapter <info:property-descriptors>.
-````
-
 ## Square brackets
 
 For multiword properties, the dot access doesn't work:

diff --git a/1-js/04-object-basics/02-object-copy/article.md b/1-js/04-object-basics/02-object-copy/article.md
@@ -1,8 +1,8 @@
 # Object references and copying
 
-One of the fundamental differences of objects versus primitives is that objects are stored and copied "by reference", as opposed to primitive values: strings, numbers, booleans, etc -- that are always copied "as a whole value".
+One of the fundamental differences of objects versus primitives is that objects are stored and copied "by reference", whereas primitive values: strings, numbers, booleans, etc -- are always copied "as a whole value".
 
-That's easy to understand if we look a bit "under a cover" of what happens when we copy a value.
+That's easy to understand if we look a bit under the hood of what happens when we copy a value.
 
 Let's start with a primitive, such as a string.
 
@@ -13,17 +13,17 @@ let message = "Hello!";
 let phrase = message;
 ```
 
-As a result we have two independent variables, each one is storing the string `"Hello!"`.
+As a result we have two independent variables, each one storing the string `"Hello!"`.
 
 ![](variable-copy-value.svg)
 
 Quite an obvious result, right?
 
 Objects are not like that.
 
-**A variable assigned to an object stores not the object itself, but its "address in memory", in other words "a reference" to it.**
+**A variable assigned to an object stores not the object itself, but its "address in memory" -- in other words "a reference" to it.**
 
-Let's look at an example of such variable:
+Let's look at an example of such a variable:
 
 ```js
 let user = {
@@ -37,13 +37,13 @@ And here's how it's actually stored in memory:
 
 The object is stored somewhere in memory (at the right of the picture), while the `user` variable (at the left) has a "reference" to it.
 
-We may think of an object variable, such as `user`, as of a sheet of paper with the address.
+We may think of an object variable, such as `user`, as like a sheet of paper with the address of the object on it.
 
-When we perform actions with the object, e.g. take a property `user.name`, JavaScript engine looks into that address and performs the operation on the actual object.
+When we perform actions with the object, e.g. take a property `user.name`, the JavaScript engine looks at what's at that address and performs the operation on the actual object.
 
 Now here's why it's important.
 
-**When an object variable is copied -- the reference is copied, the object is not duplicated.**
+**When an object variable is copied, the reference is copied, but the object itself is not duplicated.**
 
 For instance:
 
@@ -53,13 +53,13 @@ let user = { name: "John" };
 let admin = user; // copy the reference
 ```
 
-Now we have two variables, each one with the reference to the same object:
+Now we have two variables, each storing a reference to the same object:
 
 ![](variable-copy-reference.svg)
 
-As you can see, there's still one object, now with two variables that reference it.
+As you can see, there's still one object, but now with two variables that reference it.
 
-We can use any variable to access the object and modify its contents:
+We can use either variable to access the object and modify its contents:
 
 ```js run
 let user = { name: 'John' };
@@ -73,8 +73,7 @@ admin.name = 'Pete'; // changed by the "admin" reference
 alert(*!*user.name*/!*); // 'Pete', changes are seen from the "user" reference
 ```
 
-
-It's just as if we had a cabinet with two keys and used one of them (`admin`) to get into it. Then, if we later use another key (`user`) we can see changes.
+It's as if we had a cabinet with two keys and used one of them (`admin`) to get into it and make changes. Then, if we later use another key (`user`), we are still opening the same cabinet and can access the changed contents.
 
 ## Comparison by reference
 
@@ -99,15 +98,15 @@ let b = {}; // two independent objects
 alert( a == b ); // false
 ```
 
-For comparisons like `obj1 > obj2` or for a comparison against a primitive `obj == 5`, objects are converted to primitives. We'll study how object conversions work very soon, but to tell the truth, such comparisons are needed very rarely, usually they appear as a result of a programming mistake.
+For comparisons like `obj1 > obj2` or for a comparison against a primitive `obj == 5`, objects are converted to primitives. We'll study how object conversions work very soon, but to tell the truth, such comparisons are needed very rarely -- usually they appear as a result of a programming mistake.
 
 ## Cloning and merging, Object.assign
 
 So, copying an object variable creates one more reference to the same object.
 
 But what if we need to duplicate an object? Create an independent copy, a clone?
 
-That's also doable, but a little bit more difficult, because there's no built-in method for that in JavaScript. Actually, that's rarely needed. Copying by reference is good most of the time.
+That's also doable, but a little bit more difficult, because there's no built-in method for that in JavaScript. But there is rarely a need -- copying by reference is good most of the time.
 
 But if we really want that, then we need to create a new object and replicate the structure of the existing one by iterating over its properties and copying them on the primitive level.
 
@@ -226,13 +225,37 @@ user.sizes.width++;       // change a property from one place
 alert(clone.sizes.width); // 51, see the result from the other one
 ```
 
-To fix that, we should use the cloning loop that examines each value of `user[key]` and, if it's an object, then replicate its structure as well. That is called a "deep cloning".
+To fix that, we should use a cloning loop that examines each value of `user[key]` and, if it's an object, then replicate its structure as well. That is called a "deep cloning".
+
+We can use recursion to implement it. Or, to not reinvent the wheel, take an existing implementation, for instance [_.cloneDeep(obj)](https://lodash.com/docs#cloneDeep) from the JavaScript library [lodash](https://lodash.com).
+
+````smart header="Const objects can be modified"
+An important side effect of storing objects as references is that an object declared as `const` *can* be modified.
+
+For instance:
+
+```js run
+const user = {
+  name: "John"
+};
+
+*!*
+user.name = "Pete"; // (*)
+*/!*
+
+alert(user.name); // Pete
+```
+
+It might seem that the line `(*)` would cause an error, but it does not. The value of `user` is constant, it must always reference the same object, but properties of that object are free to change.
+
+In other words, the `const user` gives an error only if we try to set `user=...` as a whole.
 
-We can use recursion to implement it. Or, not to reinvent the wheel, take an existing implementation, for instance [_.cloneDeep(obj)](https://lodash.com/docs#cloneDeep) from the JavaScript library [lodash](https://lodash.com).
+That said, if we really need to make constant object properties, it's also possible, but using totally different methods. We'll mention that in the chapter <info:property-descriptors>.
+````
 
 ## Summary
 
-Objects are assigned and copied by reference. In other words, a variable stores not the "object value", but a "reference" (address in memory) for the value. So copying such a variable or passing it as a function argument copies that reference, not the object.
+Objects are assigned and copied by reference. In other words, a variable stores not the "object value", but a "reference" (address in memory) for the value. So copying such a variable or passing it as a function argument copies that reference, not the object itself.
 
 All operations via copied references (like adding/removing properties) are performed on the same single object.
 

diff --git a/1-js/04-object-basics/07-optional-chaining/article.md b/1-js/04-object-basics/07-optional-chaining/article.md
@@ -9,7 +9,7 @@ The optional chaining `?.` is a safe way to access nested object properties, eve
 
 If you've just started to read the tutorial and learn JavaScript, maybe the problem hasn't touched you yet, but it's quite common.
 
-As an example, let's say we have `user` objects that hold the information about our users. 
+As an example, let's say we have `user` objects that hold the information about our users.
 
 Most of our users have addresses in `user.address` property, with the street `user.address.street`, but some did not provide them.
 
@@ -21,7 +21,7 @@ let user = {}; // a user without "address" property
 alert(user.address.street); // Error!
 ```
 
-That's the expected result. JavaScript works like this. As `user.address` is `undefined`, an attempt to get `user.address.street` fails with an error. 
+That's the expected result. JavaScript works like this. As `user.address` is `undefined`, an attempt to get `user.address.street` fails with an error.
 
 In many practical cases we'd prefer to get `undefined` instead of an error here (meaning "no street").
 
@@ -56,7 +56,7 @@ let user = {}; // user has no address
 alert(user.address ? user.address.street ? user.address.street.name : null : null);
 ```
 
-That's just awful, one may even have problems understanding such code. 
+That's just awful, one may even have problems understanding such code.
 
 Don't even care to, as there's a better way to write it, using the `&&` operator:
 
@@ -80,7 +80,7 @@ The optional chaining `?.` stops the evaluation if the part before `?.` is `unde
 
 In other words, `value?.prop`:
 - is the same as `value.prop` if `value` exists,
-- otherwise (when `value` is `undefined/null`) it returns that `value`.
+- otherwise (when `value` is `undefined/null`) it returns `undefined`.
 
 Here's the safe way to access `user.address.street` using `?.`:
 

diff --git a/1-js/05-data-types/03-string/article.md b/1-js/05-data-types/03-string/article.md
@@ -239,7 +239,7 @@ alert( str.indexOf('widget') ); // -1, not found, the search is case-sensitive
 alert( str.indexOf("id") ); // 1, "id" is found at the position 1 (..idget with id)
 ```
 
-The optional second parameter allows us to search starting from the given position.
+The optional second parameter allows us to start searching from a given position.
 
 For instance, the first occurrence of `"id"` is at position `1`. To look for the next occurrence, let's start the search from position `2`:
 

diff --git a/1-js/05-data-types/05-array-methods/article.md b/1-js/05-data-types/05-array-methods/article.md
@@ -742,8 +742,8 @@ These methods are the most used ones, they cover 99% of use cases. But there are
 - [arr.some(fn)](mdn:js/Array/some)/[arr.every(fn)](mdn:js/Array/every) check the array.
 
   The function `fn` is called on each element of the array similar to `map`. If any/all results are `true`, returns `true`, otherwise `false`.
-  
-  These methods behave sort of like `||` and `&&` operators: if `fn`  returns a truthy value, `arr.some()` immediately returns `true` and stops iterating over the rest items; if `fn`  returns a falsy value, `arr.every()` immediately returns `false` and stops iterating over the rest items as well.
+
+  These methods behave sort of like `||` and `&&` operators: if `fn` returns a truthy value, `arr.some()` immediately returns `true` and stops iterating over the rest of items; if `fn` returns a falsy value, `arr.every()` immediately returns `false` and stops iterating over the rest of items as well.
 
   We can use `every` to compare arrays:
   ```js run