This is a sample HTML file that I would use if I want to build a very basic HTML website by hand. It was created by the guys at w3schools.com.
It’s only the skeleton that everyone can use to start a website using nothing but HTML and CSS. It looks like this:
The left and right columns take 25% of the width, and the middle column takes 50%. When viewing the page on mobile devices, the right column goes to the bottom of the page, making room for the other two. The left column usually has an Item Menu, and the middle column has the actual content of the articles. That is what designers call a responsive design.
Many more lines of code and custom CSS can be added after that, according to everyone’s taste. But the basics are there.
The file can be downloaded here: Three columns website