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stantially, here is a guide to help you decide which one is most
suitable for your needs.
To begin with, you should take into account that printers vary
in cost, speed, print quality, and other factors such as noise or
printing method. Technology is evolving so quickly that there is
always a printer for every application or need.
Dot-matrix printers use pins to print the dots required to
shape a character. A print head containing tiny pins strikes an
inked ribbon to make letters and graphics. This impact printing
technology allows shops, for example, to print multi-part forms
such as receipts and invoices, so it’s useful when self-copying pa-
per and continuous-form labels are needed. It has two important
disadvantages: noise and a relatively low resolution (from 72 to
180 dpi). They are slower than laser printers but much cheaper.
Inkjet printers generate image by spraying tiny, precise drops
of ionized ink directed by magnetic plates onto the paper. The res-
olution ranges from 300 to 1,200 dpi, suitable for small quantities
or home use.
An inkjet printer consists of a print head, ink cartridges, paper
feed assembly, belt and stabilizer bar. Inkjet printers are capable of
creating high-quality images and high-resolution photos with vivid
colours. They can work with most types of papers.
Inkjet printers have many advantages. Compared to most
printers, they are affordable, easy to use and inherently quiet. They
are ready to print and do not require any warm-up time. They are
also compact, generally requiring less space. With these features,
they are more popular as home or business printers.
There are certain disadvantages for inkjet printers. The print
head is less durable in most cases. Inkjet printer ink is expensive
and can potentially dry up, causing not only wastage of ink but al-
so blockages within the printer. Also, compared to laser printers,
they are slow to work and thus are not considered suitable for
high-volume printing.
Laser printers produce output at great speed and with a high
resolution of l,200–2,400 dpi. They scan the image with a laser
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beam and a special powder called toner is attracted to paper by an
electrostatic charge and then fused on by a hot roller. They are
constantly being improved. In terms of speed and image quality,
laser printers are preferred by experts for various reasons, for in-
stance, they have a wider range of scalable fonts than inkjets, can
emulate different language systems, and can produce high-quality
graphics.
Lasers use a page description language or PDL which describes
how to print the text and draw the images on the page. The best-
known languages are Adobe PostScript and HP Printer Control
Language.
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