Http and HTTPS port in IIS server

 80 for http

443 for https

OSI Model

 Open system interconnection

PDNTSPA

Difference between array and arraylist

 https://www.c-sharpcorner.com/article/difference-between-array-and-arraylist-in-c-sharp/

Difference between array and list in C#

 An array stores a fixed-size sequential collection of elements of the same type, whereas list is a generic collection.

https://www.tutorialspoint.com/What-is-the-difference-between-a-list-and-an-array-in-Chash

what is index in database and how to create it in database

 CREATE INDEX idx_lastname

ON Persons (LastName);

An index is a database structure that you can use to improve the performance of database activity