Identification and Authentication Failure.

A web application is like a “program” that we can use without installation as long as we have a modern standard web browser, such as Firefox, Safari, or Chrome. Consequently, instead of installing every program you need, you only need to browse the related page. The following are some examples of web applications:
Webmail such as Tutanota, Protonmail, Outlook, and Gmail
Online office suites such as Microsoft Office 365 (Word, Excel, and PowerPoint), Google Drive (Docs, Sheets, and Slides), and Zoho Office (Writer, Sheet, and Show)
Online shopping such as Amazon.com, AliExpress, and Etsy
Consider an online shopping application. The web application will read the data about the products and their details from a database server. A database is used to store information in an organized way. Examples include information about products, customers, and invoices. A database server is responsible for many functions, including reading, searching, and writing to the database. The online shopping web application might need more than one database to access, for example:
Products database: This database contains details about the products, such as name, images, specifications, and price.
Customers database: It contains all details related to customers, such as name, address, email, and phone number.
Sales database: We expect to see what each customer has purchased and how they paid in this database.