For my own purposes —making web pages— I have studied the RFCs on HTML and Style-Sheets, and studied & done some exercises on scripting.  The results are:

• HTML & Style
  • HTML & Style Summary
    Excerpt on HTML v4 (RFC) & Cascading Style Sheets v2 (CSS2)
  • Characters in HTML
    All kinds of special characters in HTML
  • Fonts in HTML
    Presentation of various fonts
  • Colors in HTML
    Presentation of some colors plus a test box
  • Block style demo
    Demo & test page for (HTML) block style (e.g. table)
  • Browser info
    Information the browser can get at
• Games
  • Tic-Tac-Toc game (Dutch:  'Boter, Kaas en Eieren', 'Kruisje-Nulletje')
    An exercise in scripting (JavaScript) and Dynamic HTML (DHTML).  Play against the computer;  in 2D you should be able to win occasionally, in 3D I don't give you much of a chance.
  • Sudoku
    This can help you to solve a Sudoku puzzle, or you can play a generated game.
    Generated game for 13 squares doesn't work yet, and not yet tested for FireFox.
• Info
  • Cursus Internet Browsen (Dutch only)
    Een korte cursus voor beginners in het 'bladeren' op internet.
  • Conditie (Dutch only)
    Calculations for training zones by heart rate, Body Mass Index (Quintillex) and (running) speed depending on distance
  • Date Calculations
    Determine the day on a date, add or subtract dates, calculate interval between dates, determine Easter for a year, generate a calendar.  Plus background and history.
  • Place look-up
    Locate places (towns/villages/hamlets/districts) in The Netherlands.
    Vind plaatsen (steden/dorpen/gehuchten/wijken) in Nederland.

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