Difference Between Null & Undefined ? 
 
Function Scope Vs. Block Scope 
 
What is Automatic Semicolon Insertion (ASI) ? 
 
Difference between Rest and Spread operator? 
 
When do you get Infinity or -Infinity as output? 
 
When do you get NaN as output? 
 
Explain must know points of arrow function. 
 
How does a "closure" work in JavaScript ? 
 
How can sum(5)(6) return 11? 
 
Memory Management & Garbage Collection 
 
How do you handle errors in JavaScript code ? 
 
Explain array & traversal in array. 
 
Add Remove Insert Replace Elements in Array 
 
How do you perform search in an array ? 
 
What is the use of map() method ? 
 
How to flatten 2D array ? 
 
How can you sort an array ? 
 
Explain Array Destructuring ? 
 
What is the purpose of call() apply() and bind()? 
 
Class Class expression & Static members 
 
Inheritance Subclassing and Extending built-in class 
 
Destructuring Object Literal 
 
Class Accessors - getter & setter methods 
 
Difference between Document Object & Window Object 
 
How to handle timer based events ? 
 
What is event bubbling & event capturing ? 
 
What is event delegation ? 
 
How to navigate through DOM ? 
 
getElementBy<idtagsclass & name>() 
 
querySelector() & querySelectorAll() 
 
ClientX/Y Vs. PageX/Y Vs. ScreenX/Y - Coordinates 
 
oncut - oncopy - onpaste Events 
 
Custom HTMLElement - First step of web component 
 
Problem without shadow DOM 
 
HTML <template> - Must know for web components 
 
Creating component template 
 
Dynamic Data with Custom Attributes 
 
Changing Attribute on Event 
 
Deleting Component - disconnectedCallback() 
 
Setter method - the right approach 
 
What is a callback function ? 
 
Explain Promise.all() Vs. Promise.allSettled() Vs. Promise.race() ? 
 
Explain functionality of async/await ? 
 
AJAX & XMLHTTPRequest (XHR) 
 
Async Iterators & Generators 
 
Introduction to debugging & Developer Tool 
 
Understanding Developer tool 
 
Debugging Pane : Watch Call stack & Scope 
 
Debugging Pane : Code Navigation 
 
Event Listener Breakpoints 
 
Conditional & Programmatic breakpoints 
 
What are DOM breakpoints? 
 
How does XHR/Fetch breakpoints work? 
 
The "console" Object Methods 
 
console.time() & related methods 
 
Introduction to Regular Expression 
 
Modifier "/m" - Multi line search 
 
Modifier "/s" & (.) Dot character class 
 
Modifier "/y" (Sticky Modifier) OR (Sticky Flag) 
 
Unicode Basics & Modifier "/u" 
 
Using modifier "/u" with Unicode property "\p" 
 
Boundary Assertions - Anchors 
 
Lookahead x(?=y) & Negative Lookahead x(?!y) 
 
Lookbehind (?<=y)x & Negative Lookbehind  (?<!y)x 
 
exec() method & lastIndex property 
 
match() & matchAll() method 
 
Assignment - Validate whether the first letter of string is in uppercase or not 
 
Assignment - Validate that a string should begin with a digit 
 
Assignment - Validate that a string should have a word containing only digits 
 
Assignment - Validate that a word should contain only letters 
 
Assignment - Validate for all uppercase character's in the string 
 
Assignment - Counting vowels & consonants in a string 
 
Assignment - Validate to find all the double words in a string 
 
Assignment - Finding a word of a specific number of letters 
 
Assignment - Validate the date format i.e. (mm/dd/yyyy) 
 
Assignment - Validate the date value along with its format 
 
Assignment - Validating email address 
 
Assignment - Validating IP address 
 
Assignment - Validating credit card number 
 
Assignment - Validate whether string is palindrome or not using regex pattern 
 
Is given value an array or not? 
 
Remove duplicate values from Array 
 
Remove nullundefined0NaN and ‘ ’ from array? 
 
Vowel & Consonant - Algorithm 
 
Array intersection and union - the ES6 way