Appoggiatura (or Grace note) :
This is a little note, placed before another note which steals its time
from the note it is linked with. When several appogiatura are linked
to a note, they are called Grace notes.
Dust removal : Erases little dots on picture.
OCR: Optical Character Recognition.
Pixel : picture dot
dpi : Dot Per Inch. Number of image dots (or pixels) per inch.
200 dpi means a 1"x1" square will contain 40,000 pixels.
Resolution : Image size in pixel and in number of possible colors
Scanner : Picture input device, which transforms a printed page
in digital data for being process by software.
Threshold : Used to transform a gray scale picture in black and
white. Separation level between black and white.
Twain : Data exchange standard between scanner and software applications.
On PC, almost all scanners are Twain compatible. On Macintosh, some old
Apple specific scanners don't follow this standard.