Update what-are-truthy-and-falsy-values.md (#2078)

Author: Yash-Handa

locale/en/knowledge/javascript-conventions/what-are-truthy-and-falsy-values.md

@@ -5,7 +5,7 @@ tags:
   - falsy
   - types
   - coercion
-title: 'What are "truthy" and "falsy" values?'
+title: 'What are "truthy" and "falsy" values?'
 difficulty: 4
 layout: knowledge-post.hbs
 ---
@@ -15,60 +15,68 @@ JavaScript is weakly typed language. That means different types can be
 used in operations and the language will try to convert the types
 until the operation makes sense.
 
-    console.log("1" > 0); // true, "1" converted to number
-    console.log(1 + "1"); // 11, 1 converted to string
+```js
+console.log("1" > 0); // true, "1" converted to number
+console.log(1 + "1"); // 11, 1 converted to string
+```
 
-Type conversion also applys when values are used in unary boolean
+Type conversion also applies when values are used in unary boolean
 operations, most notably if statements. If a value converts to the
 boolean true, then it is said to be "truthy". If it converts to false
 it is "falsy".
 
-    var myval = "value";
-    if(myval) {
-      console.log("This value is truthy");
-    }
+```js
+let myval = "value";
+if(myval) {
+  console.log("This value is truthy");
+}
 
-    myval = 0;
-    if(!myval) {
-      console.log("This value is falsy");
-    }
+myval = 0;
+if(!myval) {
+  console.log("This value is falsy");
+}
+```
 
 Since most values in javascript are truthy, e.g. objects, arrays, most
 numbers and strings, it's easier to identify all of the falsy
 values. These are:
 
-    false // obviously
-    0     // The only falsy number
-    ""    // the empty string
-    null
-    undefined
-    NaN
+```js
+false // obviously
+0     // The only falsy number
+""    // the empty string
+null
+undefined
+NaN
+```
 
 Note that all objects and arrays are truthy, even empty ones.
 
 Truthiness and Falsiness also come into play with logical
 operators. When using logical AND/OR, the values will be converted
-based on truthiness or falsyness and then the expression will resolve
+based on truthiness or falseness and then the expression will resolve
 to the last truthy value. Short circuit rules apply. Here's an
 extended example.
 
-    var first = "truthy"
-      , second = "also truthy";
+```js
+let first = "truthy",
+  second = "also truthy";
 
-    var myvalue = first && second;
-    console.log(myvalue); // "also truthy"
+let myvalue = first && second;
+console.log(myvalue); // "also truthy"
 
-    first = null;
-    second = "truthy";
+first = null;
+second = "truthy";
 
-    myvalue = first || second;
-    console.log(myvalue); // "truthy"
+myvalue = first || second;
+console.log(myvalue); // "truthy"
 
-    myvalue2 = second || first;
-    console.log(myvalue2); // "truthy"
+myvalue2 = second || first;
+console.log(myvalue2); // "truthy"
 
-    var truthy = "truthy"
-      , falsy = 0;
+let truthy = "truthy",
+  falsy = 0;
 
-    myvalue = truthy ? true : false;
-    myvalue = falsy ? true : false;
+myvalue = truthy ? true : false;
+myvalue = falsy ? true : false;
+```