HTML File

HyperText Markup Language (.html / .htm)

What is a HTML file?

An HTML file is a web page document written in HyperText Markup Language. It defines the structure of a page—headings, text, links, images, and more—and is usually paired with CSS (styling) and JavaScript (interactivity).

Common uses

Web pages and website templates
Local documentation and help files
Prototypes and landing pages
Static site pages (like your library entries)
Embedding structured content for browsers

How to open a HTML file

View: Open in any web browser (Chrome, Safari, Edge, Firefox)
Edit: VS Code, Notepad++, Sublime Text, or any text editor
Tip: If links/images break, check relative paths

Common problems

File opens as plain text (wrong extension or server header)
Broken styling because CSS/JS files are missing
Relative links/images don’t load when moved folders
Encoding issues cause weird characters
Browser caching hides recent changes when hosted

History

HTML was created in the early 1990s as the core language of the World Wide Web. Modern HTML (HTML5) supports semantic layout, media, and web app foundations when combined with CSS and JavaScript.