merging all conflicts

Author: iliakan

1-js/02-first-steps/05-types/article.md

@@ -236,7 +236,11 @@ alert(age); // "undefined"
 
 ## Ο τελεστής `typeof` [#type-typeof]
 
+<<<<<<< HEAD
 Ο τελεστής `typeof` επιστρέφει τον τύπο του ορίσματος. Είναι χρήσιμο όταν θέλουμε να επεξεργαστούμε διαφορετικές τιμές διαφορετικών τύπων ή απλώς να κάνουμε έναν γρήγορο έλεγχο.
+=======
+The `typeof` operator returns the type of the operand. It's useful when we want to process values of different types differently or just want to do a quick check.
+>>>>>>> 8d9ecb724c7df59774d1e5ffb5e5167740b7d321
 
 Υποστηρίζει δύο μορφές σύνταξης:
 

1-js/02-first-steps/08-operators/article.md

@@ -49,8 +49,14 @@
 
 Για παράδειγμα:
 ```js run
+<<<<<<< HEAD
 alert( 5 % 2 ); // 1, ένα υπόλοιπο 5 διαιρούμενο με 2
 alert( 8 % 3 ); // 2, ένα υπόλοιπο 8 διαιρούμενο με 3
+=======
+alert( 5 % 2 ); // 1, a remainder of 5 divided by 2
+alert( 8 % 3 ); // 2, a remainder of 8 divided by 3
+alert( 8 % 4 ); // 2, 0 remainder of 8 divided by 4
+>>>>>>> 8d9ecb724c7df59774d1e5ffb5e5167740b7d321
 ```
 
 ### Εκθετικό **
@@ -65,7 +71,11 @@ alert( 2 ** 3 ); // 8  (2 * 2 * 2, 3 φορές)
 alert( 2 ** 4 ); // 16 (2 * 2 * 2 * 2, 4 φορές)
 ```
 
+<<<<<<< HEAD
 Μαθηματικά, ο εκθετικός ορίζεται και για μη ακέραιους αριθμούς. Για παράδειγμα, μια τετραγωνική ρίζα εκτείνεται με το `1/2`:
+=======
+Just like in maths, the exponentiation operator is defined for non-integer numbers as well.
+>>>>>>> 8d9ecb724c7df59774d1e5ffb5e5167740b7d321
 
 
 ```js run
@@ -302,7 +312,12 @@ let n = 2;
 
 n *= 3 + 5; // right part evaluated first, same as n *= 8
 
+<<<<<<< HEAD
 alert( n ); // 16  (το σωστό μέρος αξιολογήθηκε πρώτα, το ίδια και για το n *= 8)
+=======
+alert( n ); // 16
+```
+>>>>>>> 8d9ecb724c7df59774d1e5ffb5e5167740b7d321
 
 ## Αύξηση/μείωση
 

1-js/02-first-steps/12-nullish-coalescing-operator/article.md

@@ -32,7 +32,7 @@ alert(user ?? "Anonymous"); // Anonymous (user is undefined)
 ```js run
 let user = "John";
 
-alert(user ?? "Anonymous"); // John (user is not null/udefined)
+alert(user ?? "Anonymous"); // John (user is not null/undefined)
 ```
 
 Μπορούμε επίσης να χρησιμοποιήσουμε μια ακολουθία του `??` για να επιλέξουμε την πρώτη τιμή από μια λίστα που δεν είναι `null/undefined`.

1-js/04-object-basics/09-object-toprimitive/article.md

@@ -226,7 +226,7 @@ As we know already, many operators and functions perform type conversions, e.g.
 
 If we pass an object as an argument, then there are two stages of calculations:
 1. The object is converted to a primitive (using the rules described above).
-2. If the necessary for further calculations, the resulting primitive is also converted.
+2. If necessary for further calculations, the resulting primitive is also converted.
 
 For instance:
 

1-js/05-data-types/03-string/article.md

@@ -505,7 +505,7 @@ This method actually has two additional arguments specified in [the documentatio
 
 - There are 3 types of quotes. Backticks allow a string to span multiple lines and embed expressions `${…}`.
 - We can use special characters, such as a line break `\n`.
-- To get a character, use: `[]`.
+- To get a character, use: `[]` or `at` method.
 - To get a substring, use: `slice` or `substring`.
 - To lowercase/uppercase a string, use: `toLowerCase/toUpperCase`.
 - To look for a substring, use: `indexOf`, or `includes/startsWith/endsWith` for simple checks.
@@ -519,4 +519,4 @@ There are several other helpful methods in strings:
 
 Strings also have methods for doing search/replace with regular expressions. But that's big topic, so it's explained in a separate tutorial section <info:regular-expressions>.
 
-Also, as of now it's important to know that strings are based on Unicode encoding, and hence there're issues with comparisons. There's more about Unicode in the chapter <info:unicode>.
+Also, as of now it's important to know that strings are based on Unicode encoding, and hence there're issues with comparisons. There's more about Unicode in the chapter <info:unicode>.

1-js/05-data-types/07-map-set/article.md

@@ -10,17 +10,17 @@ But that's not enough for real life. That's why `Map` and `Set` also exist.
 
 ## Map
 
-[Map](mdn:js/Map) is a collection of keyed data items, just like an `Object`. But the main difference is that `Map` allows keys of any type.
+[Map](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map) is a collection of keyed data items, just like an `Object`. But the main difference is that `Map` allows keys of any type.
 
 Methods and properties are:
 
-- `new Map()` -- creates the map.
-- [`map.set(key, value)`](mdn:js/Map/set) -- stores the value by the key.
-- [`map.get(key)`](mdn:js/Map/get) -- returns the value by the key, `undefined` if `key` doesn't exist in map.
-- [`map.has(key)`](mdn:js/Map/has) -- returns `true` if the `key` exists, `false` otherwise.
-- [`map.delete(key)`](mdn:js/Map/delete) -- removes the value by the key.
-- [`map.clear()`](mdn:js/Map/clear) -- removes everything from the map.
-- [`map.size`](mdn:js/Map/size) -- returns the current element count.
+- [`new Map()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/Map) -- creates the map.
+- [`map.set(key, value)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/set) -- stores the value by the key.
+- [`map.get(key)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/get) -- returns the value by the key, `undefined` if `key` doesn't exist in map.
+- [`map.has(key)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/has) -- returns `true` if the `key` exists, `false` otherwise.
+- [`map.delete(key)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/delete) -- removes the value by the key.
+- [`map.clear()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/clear) -- removes everything from the map.
+- [`map.size`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/size) -- returns the current element count.
 
 For instance:
 
@@ -100,14 +100,13 @@ map.set('1', 'str1')
 ```
 ````
 
-
 ## Iteration over Map
 
 For looping over a `map`, there are 3 methods:
 
-- [`map.keys()`](mdn:js/Map/keys) -- returns an iterable for keys,
-- [`map.values()`](mdn:js/Map/values) -- returns an iterable for values,
-- [`map.entries()`](mdn:js/Map/entries) -- returns an iterable for entries `[key, value]`, it's used by default in `for..of`.
+- [`map.keys()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/keys) -- returns an iterable for keys,
+- [`map.values()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/values) -- returns an iterable for values,
+- [`map.entries()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/entries) -- returns an iterable for entries `[key, value]`, it's used by default in `for..of`.
 
 For instance:
 
@@ -162,7 +161,7 @@ let map = new Map([
 alert( map.get('1') ); // str1
 ```
 
-If we have a plain object, and we'd like to create a `Map` from it, then we can use built-in method [Object.entries(obj)](mdn:js/Object/entries) that returns an array of key/value pairs for an object exactly in that format.
+If we have a plain object, and we'd like to create a `Map` from it, then we can use built-in method [Object.entries(obj)](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/entries) that returns an array of key/value pairs for an object exactly in that format.
 
 So we can create a map from an object like this:
 
@@ -233,16 +232,16 @@ That's the same, because `Object.fromEntries` expects an iterable object as the
 
 ## Set
 
-A `Set` is a special type collection - "set of values" (without keys), where each value may occur only once.
+A [`Set`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set) is a special type collection - "set of values" (without keys), where each value may occur only once.
 
 Its main methods are:
 
-- `new Set(iterable)` -- creates the set, and if an `iterable` object is provided (usually an array), copies values from it into the set.
-- [`set.add(value)`](mdn:js/Set/add) -- adds a value, returns the set itself.
-- [`set.delete(value)`](mdn:js/Set/delete) -- removes the value, returns `true` if `value` existed at the moment of the call, otherwise `false`.
-- [`set.has(value)`](mdn:js/Set/has) -- returns `true` if the value exists in the set, otherwise `false`.
-- [`set.clear()`](mdn:js/Set/clear) -- removes everything from the set.
-- [`set.size`](mdn:js/Set/size) -- is the elements count.
+- [`new Set([iterable])`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/Set) -- creates the set, and if an `iterable` object is provided (usually an array), copies values from it into the set.
+- [`set.add(value)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/add) -- adds a value, returns the set itself.
+- [`set.delete(value)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/delete) -- removes the value, returns `true` if `value` existed at the moment of the call, otherwise `false`.
+- [`set.has(value)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/has) -- returns `true` if the value exists in the set, otherwise `false`.
+- [`set.clear()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/clear) -- removes everything from the set.
+- [`set.size`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/size) -- is the elements count.
 
 The main feature is that repeated calls of `set.add(value)` with the same value don't do anything. That's the reason why each value appears in a `Set` only once.
 
@@ -272,7 +271,7 @@ for (let user of set) {
 }
 ```
 
-The alternative to `Set` could be an array of users, and the code to check for duplicates on every insertion using [arr.find](mdn:js/Array/find). But the performance would be much worse, because this method walks through the whole array checking every element. `Set` is much better optimized internally for uniqueness checks.
+The alternative to `Set` could be an array of users, and the code to check for duplicates on every insertion using [arr.find](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find). But the performance would be much worse, because this method walks through the whole array checking every element. `Set` is much better optimized internally for uniqueness checks.
 
 ## Iteration over Set
 
@@ -295,38 +294,38 @@ That's for compatibility with `Map` where the callback passed `forEach` has thre
 
 The same methods `Map` has for iterators are also supported:
 
-- [`set.keys()`](mdn:js/Set/keys) -- returns an iterable object for values,
-- [`set.values()`](mdn:js/Set/values) -- same as `set.keys()`, for compatibility with `Map`,
-- [`set.entries()`](mdn:js/Set/entries) -- returns an iterable object for entries `[value, value]`, exists for compatibility with `Map`.
+- [`set.keys()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/keys) -- returns an iterable object for values,
+- [`set.values()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/values) -- same as `set.keys()`, for compatibility with `Map`,
+- [`set.entries()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/entries) -- returns an iterable object for entries `[value, value]`, exists for compatibility with `Map`.
 
 ## Summary
 
-`Map` -- is a collection of keyed values.
+[`Map`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map) -- is a collection of keyed values.
 
 Methods and properties:
 
-- `new Map([iterable])` -- creates the map, with optional `iterable` (e.g. array) of `[key,value]` pairs for initialization.
-- [`map.set(key, value)`](mdn:js/Map/set) -- stores the value by the key, returns the map itself.
-- [`map.get(key)`](mdn:js/Map/get) -- returns the value by the key, `undefined` if `key` doesn't exist in map.
-- [`map.has(key)`](mdn:js/Map/has) -- returns `true` if the `key` exists, `false` otherwise.
-- [`map.delete(key)`](mdn:js/Map/delete) -- removes the value by the key, returns `true` if `key` existed at the moment of the call, otherwise `false`.
-- [`map.clear()`](mdn:js/Map/clear) -- removes everything from the map.
-- [`map.size`](mdn:js/Map/size) -- returns the current element count.
+- [`new Map([iterable])`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/Map) -- creates the map, with optional `iterable` (e.g. array) of `[key,value]` pairs for initialization.
+- [`map.set(key, value)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/set) -- stores the value by the key, returns the map itself.
+- [`map.get(key)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/get) -- returns the value by the key, `undefined` if `key` doesn't exist in map.
+- [`map.has(key)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/has) -- returns `true` if the `key` exists, `false` otherwise.
+- [`map.delete(key)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/delete) -- removes the value by the key, returns `true` if `key` existed at the moment of the call, otherwise `false`.
+- [`map.clear()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/clear) -- removes everything from the map.
+- [`map.size`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/size) -- returns the current element count.
 
 The differences from a regular `Object`:
 
 - Any keys, objects can be keys.
 - Additional convenient methods, the `size` property.
 
-`Set` -- is a collection of unique values.
+[`Set`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set) -- is a collection of unique values.
 
 Methods and properties:
 
-- `new Set([iterable])` -- creates the set, with optional `iterable` (e.g. array) of values for initialization.
-- [`set.add(value)`](mdn:js/Set/add) -- adds a value (does nothing if `value` exists), returns the set itself.
-- [`set.delete(value)`](mdn:js/Set/delete) -- removes the value, returns `true` if `value` existed at the moment of the call, otherwise `false`.
-- [`set.has(value)`](mdn:js/Set/has) -- returns `true` if the value exists in the set, otherwise `false`.
-- [`set.clear()`](mdn:js/Set/clear) -- removes everything from the set.
-- [`set.size`](mdn:js/Set/size) -- is the elements count.
+- [`new Set([iterable])`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/Set) -- creates the set, with optional `iterable` (e.g. array) of values for initialization.
+- [`set.add(value)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/add) -- adds a value (does nothing if `value` exists), returns the set itself.
+- [`set.delete(value)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/delete) -- removes the value, returns `true` if `value` existed at the moment of the call, otherwise `false`.
+- [`set.has(value)`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/has) -- returns `true` if the value exists in the set, otherwise `false`.
+- [`set.clear()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/clear) -- removes everything from the set.
+- [`set.size`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/size) -- is the elements count.
 
 Iteration over `Map` and `Set` is always in the insertion order, so we can't say that these collections are unordered, but we can't reorder elements or directly get an element by its number.