How to explain VIM's modes to people?

For those coming from graphical editors, this might be helpful:

In graphical user interfaces you have two input devices - the keyboard and mouse. You use the keyboard for most editing, and the mouse for moving around the document.

In VIM you have two modes that both use the keyboard. One is for moving around the document, and one is for editing the text. Normal mode is akin to using the mouse - except you're going to use the keyboard to move around the document. Edit mode is for adding text, again using the keyboard.

vim has two modes, one that beeps at you, and one that destroys your document.

But honestly, I think the simplest method would be:

• control mode: In this mode, you don't type into the file, but rather give control type statements (remove this many lines, replace this word, etc.).

• typing / insert mode: Here, you "normally" type into the file.