HP LaserJet 1100 All-in-One Printer series - Manual (Page 16)

6 Chapter 1 Getting to know the printer EN
Printer paper output paths
Paper output bin
The paper output bin is located on the front of the printer. Printed
paper will be collected here in the correct sequence when the paper-
output lever is in the up position. Use the output bin when printing
large, collated documents or when copying documents so that the
original is separated from the copies.
Straight-through paper output path
The straight through paper output path is useful when printing
envelopes, transparencies, heavy media, or anything that tends to
curl when printed. Printed paper will stack in reverse order with the
paper-output lever down.