Craig mentioned this site before he disappeared into a snow bank. I was going to link to it then, but I must have wandered off somewhere. Then Mark mentioned it and it all came back in a rush. This is a must site for those who are fascinated with words and their representation. That should include anyone who can write. Right?

Omniglot

In A History of Writing, Steven Roger Fischer argues that no one definition of writing can cover all the writing systems that exist and have ever existed. Instead he states that a 'complete writing' system should fullfill all the following criteria:

Complete writing must have as its purpose communication;

Complete writing must consist of artificial graphic marks on a durable or electronic surface;

Complete writing must use marks that relate conventionally to articulate speech (the systematic arrangement of significant vocal sounds) or electronic programing in such a way that communication is achieved.
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So how many different marks are there? This site shows some of the amazing variety.