Primitive Data Type

Always used in primitive type data. JavaScript is all these objects. Any number type number can be a decimal if it starts with a number

var newNumber = 13;
var otherNumber = 11.20;

Non-Primitive

Value off time of non primitive data type is not saved. They also have some property array object functions.JavaScript We use the type of operator to view any data type.

Try..catch

As much as we are experts in the program. The program may stop due to a mistake somewhere. Many times the user gives wrong input error. Suppose we get an error in line 4 then not a single line will work as many lines as there are below. We test the code with try and handle it with error. If we make an error at run time, then try catch then handles the error.

Coding Style

The code should be sorted with many beautiful structures. Then it is not a problem to understand the quote of the code that is checked.

Comment

When we code, some of the code is very important. It is better to comment on those important places. What happens if I comment that the ones I will comment on will be seen many days or many years later and it will be understood what I was doing in that place. And the comment I will make will never show the output. Good to comment

Statement & Expression

Some lines sometimes produce value in our code. As 5 + 5 equal se 10. And there are some codes that only take action. Such as conditional statements. They don’t produce any value, just take certain actions. Based on these, we distinguish statements and expressions. Directly producing expression value in Bengali and the statement only takes action.

This Keyword

The trickiest and confusing topic or word in JavaScript is.Generally, value is determined this based on how a function is being called. And its value is determined during execution.

Strict

JavaScript has some amazing uses that this streak mode is introduced to overcome. There is a need to be careful when using stick mode. Many environmental browsers may not have a strike.

Scope

Scope JavaScript is an important thing. We need to know where we can or cannot use the variable functions we have declared. Scope There are generally two types of local scope, global scope

Var Declarations and Hoisting

variables declared with var they are hosted to the top of the function or global scope if declared outside a function. var declarations are treated as if they are hoisted to the top of the function as enclosing block or to the global scope if they are declared outside a function.

Block Binding in Loops

The block level is very important when interacting with JavaScript people. It is best practice to use the net instead of clowns because marriage is being posted.

Global Block Bindings

When the beer is used in the perimeter, a new global variable is created that is a property of a global object.

Function with Unnamed Parameters

JavaScript function parameters that are passed without defining are inspected through the object although in many cases the arguments should be inspected works well but the object may be somewhat difficult to work with.

Block-Level Functions

Allows ES6 block level functions in JavaScript to be used on the function.