This online project named OpenVim lets you practice with a Vim interface for learning.
The development team tells us:
OpenVim is a web-based project to let people quickly have a taste what kind of an editor Vim is. Vim is considered to be very useful but can feel devastatingly opaque at first. Hopefully this tutorial makes people feel more comfortable to give it a chance.
OpenVim is based on a custom engine that interprets vim commands. Fun fact: the engine operates directly on the dom but could be easily refactored to a model that is not view-dependent.
The GitHub project can be found here.
The webpage starts with a great online tutorial in an interactive way.
Users can understand well how can use the vim editor.