Technical Bricks For Building Websites

What are the technical key considerations needed for building websites?

In overall, we need the following technical bricks to build the websites

1. Software Design(including choosing the software technologies which comply with modern technologies)
2. Development Environment Setup (including source version control, coding standards…etc.)
3. Authentication and Authorization(for frontend and backend layers depends upon the type of websites)
4. Security (including for preventing XSS, CSRF…etc.)
5. Exception Handling and Logging (including custom error messages, page not found error page…etc.)
6. Database Design (including normalization, store procedures, triggers, views…etc.)
7. Caching (for improving the performance of the web site)
8. Testing (including unit test, performance, Data Driven Testing (DDT)...etc.)
9. Hosting Environment Plan
10. Documentation (including deployment, support…etc. documentations)

Next, do we need necessarily all the above bricks for building websites?  

Yes. But no. It's depends upon the type of websites.