Notes

V-8
https://www.javatpoint.com/nodejs-v8

Clients Send request to Web Server.

Node JS Web Server internally maintains a Limited Thread pool to provide services to the Client Requests.

Node JS Web Server receives those requests and places them into a Queue. It is known as “Event Queue”.

Node JS Web Server internally has a Component, known as “Event Loop”. it uses indefinite loop to receive requests and process them.

Event Loop uses Single Thread only. It is main heart of Node JS Platform Processing Model.

Even Loop checks any Client Request is placed in Event Queue. If no, then wait for incoming requests for indefinitely.

If yes, then pick up one Client Request from Event Queue

Starts process that Client Request

If that Client Request Does Not requires any Blocking IO Operations, then process everything, prepare response and send it back to client.

If that Client Request requires some Blocking IO Operations like interacting
with Database, File System, External Services then it will follow different approach

Checks Threads availability from Internal Thread Pool

Picks up one Thread and assign this Client Request to that thread.

That Thread is responsible for taking that request, process it, perform Blocking IO operations, prepare response and send it back to the Event Loop

Event Loop in turn, sends that Response to the respective Client.

Async functions will always return a value.Using async simply implies that a promise will be returned

Cookies= are small blocks of data created by a web server while a user is browsing a website and placed on the user's computer or other device by the user’s web browser
Cookies are client-side files on a local computer that hold user information
Sessions are server-side files that contain user data

Cookies are client-side files on a local computer that hold user information. Sessions are server-side files that contain user data.

Local Storage has no expiration date.
Session Storage data are gone when you close the browser tab
Means data store in it*

session storage only keeps data for a particular session.

authentication is the process of verifying who a user is. and authorization is the process of verifying what they have access to.

Memoization ensures that method does not execute more than once for same inputs by storing the results in the data structure which speeds up application.

asynchronous means non-blocking operations