wip: add more questions

src/data/question-groups/javascript/content/explicit-binding.md

@@ -0,0 +1,19 @@
+Explicit binding is a way to explicitly state what the `this` keyword is going to be bound to using `call`, `apply` or `bind` methods of a function.
+
+```js
+const roadmap = {
+  name: 'JavaScript',
+};
+
+function printName() {
+  console.log(this.name);
+}
+
+printName.call(roadmap); // JavaScript
+printName.apply(roadmap); // JavaScript
+
+const printRoadmapName = printName.bind(roadmap);
+printRoadmapName(); // JavaScript
+```
+
+In the above example, the `this` keyword inside the `printName()` function is explicitly bound to the `roadmap` object using `call`, `apply` or `bind` methods.

src/data/question-groups/javascript/content/set-interval.md

@@ -0,0 +1,17 @@
+You can run some codes on interval using `setInterval` function in JavaScript. It accepts a function and a time interval in milliseconds. It returns a unique id which you can use to clear the interval using `clearInterval` function.
+
+```js
+const intervalId = setInterval(() => {
+  console.log('Hello World');
+}, 1000);
+
+// Output:
+// Hello World
+// Hello World
+```
+
+In the above code, the `setInterval` function runs the callback function every 1000 milliseconds (1 second) and prints `Hello World` to the console. It returns a unique id which you can use to clear the interval using `clearInterval` function.
+
+```js
+clearInterval(intervalId);
+```

src/data/question-groups/javascript/content/set-timeout.md

@@ -0,0 +1,16 @@
+To run a piece of code after a certain time, you can use `setTimeout` function in JavaScript. It accepts a function and a time interval in milliseconds. It returns a unique id which you can use to clear the timeout using `clearTimeout` function.
+
+```js
+const timeoutId = setTimeout(() => {
+  console.log('Hello World');
+}, 1000);
+
+// Output:
+// Hello World
+```
+
+In the above code, the `setTimeout` function runs the callback function after 1000 milliseconds (1 second) and prints `Hello World` to the console. It returns a unique id which you can use to clear the timeout using `clearTimeout` function.
+
+```js
+clearTimeout(timeoutId);
+```

src/data/question-groups/javascript/javascript.md

@@ -211,4 +211,24 @@ questions:
     topics:
       - 'Core'
       - 'Advanced'
+  - question: What is Type Casting?
+    answer: Type conversion (or typecasting) means transfer of data from one data type to another. Implicit conversion happens when the compiler (for compiled languages) or runtime (for script languages like `JavaScript`) automatically converts data types.
+    topics:
+      - 'Core'
+      - 'Intermediate'
+  - question: What are Explicit binding in JavaScript?
+    answer: explicit-binding.md
+    topics:
+      - 'Core'
+      - 'Advanced'
+  - question: How to run a piece of code after a specific time interval?
+    answer: set-interval.md
+    topics:
+      - 'Core'
+      - 'Beginner'
+  - question: How to run a piece of code only once after a specific time?
+    answer: set-timeout.md
+    topics:
+      - 'Core'
+      - 'Beginner'
 ---