- Layout
- Tags
- Semantic tags
- Text
- Form
- Tables
- Lists
- meta
- Audio and Video
- Image and objects
- Other
- colours
- fonts
- forms
- backgrounds
- images
- pseudo:classes
- pseudo::elements
- attributes and values
- length units
- inheritance
- Positioning
- Flexbox Grid Inline Block Floats
- Misc : SVG,
- Cookies
- Local Storage
- Ruby
- Python
- Perl
- Go / Elixir / Crystal / Nim
- Java / Scala and others
- Files
- CSV
- Text
- YAML or JSON or others
- SQL or RDBMS
- SQLite3
- Non SQL databases
- Redis
- Internet Protocols : HTTP/S, FTP, IMAP, QUIC
- TCP and UDP
- IP addresses
- Routers and Routing Algorithms
- DNS and Domain names
- Hosting
- Content Delivery Network _ CDN
- Internet Service Provider _ ISP
- MIME Types
- Encryption : SSL, TLS
- Page load
- Page size
- You shall not use CSS Frameworks and JavaScript Frameworks unless on a gunpoint