UA
UMB
unavailable
unavailable option
underline
underscore
undo
unformatted
unfreeze all columns
ungroup
unipolar
unit
unit matrix
unit of measure
UNIVAC I
universal
unknown CD
unmodified
unpack
unreadable CD
unrecoverable
Unseen Impression Filter
unselect all
UPC
update
updated
updating
upgrade
upgraded
upload
url
URL channel
usb
user
user documentation
user name
user profile
user state
user terminal
username
utility program
UV light