Reading Usable Help
@UsableHelp on Twitter
Gordon R. Meyer
Documentation for getting a grip
When technology is brand new the most basic elements of using it need to be covered, such as how to hold the device. At one time even cameras were new and in Scanning Around With Gene: How to Look Like a Real Photographer you can see how users were taught to hold their gadgets. Compare this with How to Hold a Mouse and the inclusive but silly How to Hold a Mouse With Your Left Hand.
See also Dial M for Mouse for discussion about dialing a telephone and Apple's mouse tutorials.