Q: Difference between var, let, const

Ans:

let is used to declare the variable or initialize a variable. let variable can be updated in future.Its block scope and we cannot redeclare it. let cannot redeclare a value but we can update the value.

var is just like let but var is used to declare a variable value at top of the program, its hoisted. var will be redeclared and we can update its value.

Const means constant and const is strict. Const Initilizing and declaring a variable at a time. const should be declared and intialized. Cannot redeclare the variable again.

Q: Difference between arrow function and regular function.

Ans: It's a shorter syntax and thus requires less code. Arrow functions are best for callbacks or methods like map , reduce , or forEach. Regular functions is good but this is not perfect to use on code because of it takes large code to write and on the other hand the arrow funciton takes few codes. And there have tons of difference between arrow and regular funciton. The main thing is less code of arrow function.

Q: Difference between map, filter, forEach, find

Ans: Map function is used for joining for each data. 'Filter' it's names says that what filter does. its filtering data. forEach is an amazing funciton to use it's just like a map function but it only deliver each data. 'find' function is finding data.

Q: Why you should use template string

Ans: template string is an amazing things on JavaScript I just fall in love with this feature. It's make our life easy. In template string we can define multiple thing and other qutes don't. we can write text and also variable and also we can write code on templete string. That's Why we should use templete string