posted by kellie .
the def of the shift key?
"The shift key is a modifier key on a keyboard, used to type capital letters and other alternate "upper" characters."
From wikipedia =)
Depending on what applications you are using, the shift key can modify other commands. for example, in Adobe Photoshop it allows you to make more selections of areas with out losing the previous selctions.
I hope this helps a little more. Thanks for asking.