Data Representation

Data Representation Study Sheet
A summary of all the numeric conversions, with examples.
Conversion charts
One page reference sheet with binary/octal and binary/hexadecimal conversion tables and powers of 2.
Number Systems Tutorial
A brief tutorial on number systems.
Quick conversions
A quick method of converting binary numbers to decimal.
Binary, octal, and hexadecimal numbers.
Converting Binary, Decimal, and Hexadecimal Notation
Another page discussing base conversions.
How Many Bytes…
How many bytes does it take to store _____?
Memory Sizes Explained
ASCII/ANSI symbol table
ASCII definition from Wikipedia
Web site with links to lists of alt-codes for all available characters and how to type them on Windows, Mac OS/X, and Linux systems.
Also include links to Facebook/MySpace text & symbol generators.
Unicode organization home page
includes background information and the current working definition. 
Unicode & UTF-8 Character Sets
From Smashing Magazine