Over the past century, there have been many discoveries when it comes to methods of printing. From Gutenberg's earliest printing press to our present day personal computer printer, the level of sophistication may have changed but the essence remains the same. Printing is not only a mechanical function done by printing machine devices; it is an art form. Printing allows art to be replicated and immortalized. It allows ideas to be pumped into the world by printing the written word.
Printing out documents is fast and easy, and once it is done the resulting printout is also known as your ‘hard copy’. There are two types of printing machine devices:
Impact Printers. These types of printers use a print head containing metal pins, which strike an inked ribbon placed between the print head and the paper. It functions much like a “typewriter”. Some only have 9 heads, but print heads can have up to 24 metal pins that provide better resolution for your printouts or hard copy. Examples of impact printers are the Dot Matrix Printer and Daisy Wheel.
- Dot Matrix Printers. These printers form characters from a matrix of dots. This is the cheapest and noisiest type of printer. The quality of printouts is poor. These are ideally used only for carbon copy printouts. It runs fast so it saves time. It can print up to 500 characters per second.
- Daisy Wheel. Molded metal characters are used to print on paper using a hammer and a ribbon. This functions and is similar in mechanism to a basic typewriter. Printing is quite slow (about 90 characters per second). The quality of printing output when you use this device is similar to that of an electronic typewriter. Because the characters on the wheel are fixed, changing the font or size of characters would require the wheel to be changed.
Non-Impact Printers. Non-impact printers work in a quieter way than impact printers. This is because their printer heads don’t strike the paper at all during the printing process.
- Thermal Printer. This type of printer uses heat by exposing a special kind of thermal paper to heated elements to produce darkened dots that form characters. The standard of print produced is poor. Thermal paper tends to darken or fade over time. This is only used for documents or pieces of paper intended for temporary use and not for those that are intended for indefinite filing. A word of advice—if you want to keep a document printed in thermal paper for a long time, photocopy it and keep this copy instead.
- Laser Printer. This type of printer uses a laser beam (hence the term) and dry powdered ink to form characters on paper. The outcome is very good. Laser printers have been known to generate good quality graphic images as well.
- Inkjet Printer. This type of printer is the best one to use to make colored printouts. It makes use of color cartridges of magenta, yellow and cyan to create different color tones. This allows good quality and cheap printing.
There are also other methods of printing used by printing companies. An example of a printing technique is offset printing. This involves a process that makes use of screen printing equipment. Offset printing is done by transferring (or offsetting) an inked image from a plate to a rubber blanket and then to the printing surface by using a machine press. Offset printing is the most common printing technique used in large, commercial printing.
Offset printing is a cheap way to get bulk printing jobs done. Most modern offset printing companies use a computer to plate method instead of the more costly computer to film method. Over the last few decades, flexography (used for printing on almost any type of substrate, which includes metallic films, plastic, paper and cellophane) has become the most popularly used form of printing because it’s fast and cheap. Offset printing may also be used in combination with a lithographic process that basically keeps non-printing areas ink-free.