Characters:

Unicode

Unicode Home Page, standards organization.

BMP

Map of BMP, lowest Unicode characters. The map is divided into blocks, each with a link to a pdf file define the contents of the block.

Omni

Website with every form of writing ever used, collected by Simon Ager.

UTF-8

The most authoritative definition of UTF-8. But for a more readable article, see Wikipedia on UTF-8. The code is defined so that character searches can not get a mismatch because of overlap, but there is more than one way to represent some characters. Full conformance to the standard requires using the shortest representation.

fonts

List of fonts available by default in Mozilla.

omnicode

Unicode table, java generated.

entities

Character Entity List for XHTML 1.0

block

This block, set entirely with a monospaced font, shows that block graphics cannot be used in html.

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┣━━━╋━━━┫
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┗━━━┻━━━┛

abcdefghijklmnopqrstuvwxyz
bcdefghijklmnopqrstuvwxyza
cdefghijklmnopqrstuvwxyzab
defghijklmnopqrstuvwxyzabc
efghijklmnopqrstuvwxyzabcd
fghijklmnopqrstuvwxyzabcde
ghijklmnopqrstuvwxyzabcdef
hijklmnopqrstuvwxyzabcdefg