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Printers are the main topic for this web-site. Printers are nothing without some kind of paper so this section looks at paper making and handling techniques.
The first three generations of computer relied on paper as their output. Printouts were usually ephemeral - not expected to last more than a year or so because the data would change.
Screen based terminals and PCs gave an alternate way of looking at information. Curiously computer paper consumption actually increased as more information moved to machine. One explanation is that screens aren't actually as good as they look so people prefered printouts.
Digital print is taking over. Computer printers can generate crude text, pages for books, diagrams, photographs and artwork. Some of these tasks need long-lasting paper and inks that should be stable for a hundred years. (People expect this longevity of print).
Paper presents itself as a fairly simple material. Paper actually involves a series of agricultural, chemical, marketing and transport actions which have all sorts of social and economic impact.
Paper Making. 
Basic Idea - flat amorphous felt of compressed interlocked and adhered fibres.
Historic Process - parchment, vellum and cloth papers. Too expensive for mass literacy.
Modern process - trees chipped and fed into the Kraft process to make pulp, then a Fourdrinier machine to make a web of paper.
Trees - spruce or similar trees about 15 metres tall and 150mm diameter harvested in 4 to 8 foot lengths.
Debarking drum - leaves bare wood.
Chippers - break logs into fairly regular small lumps.
Pulp making - Cellulose is wanted. Lignin is usually removed and discarded.
Kraft Process - pressure vessels loaded with sodium hyroxide and sodium sulphide remove lignin. Lignin removed as black liquor.
Refiners break down softened chips. Fibers partially break down and fibrils released. Chlorine bleaches used until pulp reaches the required brightness.
Paper Making uses virgin pulp, waste paper "broke" sizing fillers and colourings.
Pulp mixture diluted to thin slurry then processed by hand or by machine.
Handmade Paper - popular with artists and designers.
Paper Making Machines - usually known as a Fourdrinier machine .
Machine Made Paper - usually a Fourdrinier Machine.
Headbox releases pulp slurry onto a wire mesh conveyor.
Fourdrinier table vibrates material and applies some vacuum releasing water through mesh.
Press rollers squeeze out more water at nip points.
Drying is done by steam heated rollers.
Calender rollers smooth the paper to the required finish.
The finish matches the intended printing task.
Variation in the process -
Web paper - rolls stored or shipped to print works. Cut to required shape or made into rolls or fanfold forms.
Non-print uses cardboard, packaging and sanitary applications.
Environment and Recycled Fibre.
Paper Sizes.
ISO Paper Sizes - A, B and C series.
Grammage -Paper thickness normally given as weight in grams per square metre.
Quantity - 500 sheets is a ream.
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Paper Styles & Use - people often have strong views on how documents should look.
Nature of Paper - fine fibers bound by cellulose, sized with kaolin and polished.
Paper Shapes -made in rolls. Can be web fed or sheet fed. Office printers use pre-cut.
Paper Cutting - can be by guillotine, saw or water jet.
Paper Grades - commonly a 3-fold price difference on A4 80gsm copier paper.
Printers & Paper. In principle any technology might take any paper. In practice each design takes a limited range. The printer needs to know the shape of the page and sense top of page.
VFU and Control Languages allow the computer and or printer to lay out pages.
Cut sheet paper - A4, Letter and Legal.
Tractor Feed -sprocket holes at half-inch intervals. Usually in boxes of 2,000 sheets.
Pull Tractors - feed paper after the platen - reliable but can't do sheet on demand.
Push Tractors - give sheet on demand paper feed.
Pre Printed Forms - multi-part business forms give forensically verifiable copy.
Accounting Software - special packages can be paid for by copyright forms.
Cut Sheet Feeding - more complex. Pickup rollers, feed rollers, sequence of actions.
Paper Handling Options - printer can be part of a system.
Duplex - makes document look professional and saves paper.
Multiple Trays - can be used for letterhead, plain and envelope - can be a big time saver.
White Paper Offices - Letterhead.
White Paper Offices - Forms.
Paper Production - Paper presents itself as a fairly simple material. Paper actually involves a series of agricultural, chemical, marketing and transport actions which have all sorts of social, environmental and economic impacts.
Basic Idea - flat material made from compressed, interlocked and adhered fibre. Cloth has stucture and texture. Paper is amorphous and has less surface texture.
Historic Process - discovered in China and kept secret.
Modern Process -
Kraft Process -
Fourdrinier Process -