drag and drop

A common method for manipulating files (and sometimes text)

under a graphical user interface or WIMP environment. The

user moves the pointer over an icon representing a file and

presses a mouse button. He holds the button down while moving

the pointer (dragging the file) to another place, usually a

directory viewer or an icon for some application program,

and then releases the button (dropping the file). The meaning

of this action can often be modified by holding certain keys

on the keyboard at the same time.

Some systems also use this technique for objects other than

files, e.g. portions of text in a word processor.

The biggest problem with drag and drop is does it mean "copy"

or "move"? The answer to this question is not intuitively

evident, and there is no consensus for which is the right

answer. The same vendor even makes it move in some cases and

copy in others. Not being sure whether an operation is copy

or move will cause you to check very often, perhaps every time

if you need to be certain. Mistakes can be costly. People

make mistakes all the time with drag and drop. Humancomputer interaction studies show a higher failure rate for

such operations, but also a higher "forgiveness rate" (users

think "silly me") than failures with commands (users think

"stupid machine"). Overall, drag and drop took some 40 times

longer to do than single-key commands.

[Erik Naggum [email protected]]