- h moves the cursor left
- j moves the cursor down
- k moves the cursor up
- l moves the cursor right
this of course happens only in command mode...
Back in those days not every ASCII terminal had cursor keys to move about that blinking thing. Sometimes it didn't even blink, it was a solid inverted rectangle, preferably green or amber. Some other terminals had an underscore instead.
An interesting fact is that the Sinclair ZX Spectrum cursor keys were laid out in the same way. Cursor movement used too be accessed through the 5 6 7 8 keys. Coincidence?