[the_duke]

You can write self contained, single file .html documents just fine.

[pjmlp]

Not when you need images, and if you need to display 3D data you are required to actually serve textures over a server.

[elcomet]

You can embed images in the HTML as well

[pjmlp]

Sure, if you resort to tricks like Base64 encoding in strings, that won't do for WebGL textures though.