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1. BBC Dance Mat Typing
This website is a little silly, but it is fun!
Does not require registration
Requires registration, but gives more personalized lessons.
Here's a neat website that doesn't require any registration to get started. It's easy to navigate and good for any level of typing proficiency, from those just getting started to the most accomplished typist. They even offer certifications and specialty lessons!
If you are able to download an actual software program, Mavis Beacon Teaches Typing is a classic program that works well and has taught thousands of people how to type.