NCR Sets - What are they?
NCR Sets are a Carbonless NCR ["No Carbon Required"] product in it's most basic form - loose sheets. They are usually, but not always, glued at the top in their individual parts. The printing industry call this sort of glue, "fan-apart" glue, as in the factory a wall of NCR paper is literally painted with the glue, it dries, cures, and to separate all the paper magically into individual NCR Sets, the Finisher fans the glued wall of the tower of paper.
NCR Sets are not as durable for on-the-road or site work and are mostly used in an office environment where durability is not a concern.
NCR Pads - What are they?
NCR Pads are essentially the same as NCR Sets except all Sets are glued together into a peel-able Pad.
NCR Pads would usually contain 50 sets. They work in a very similar way to a standard notebook were you can peel off the pages from the pad. They feature a backing board [we call it a "strawboard back" within the printing industry] to provide extra rigidity and support as well as keeping the pages in good condition. They can also come with a writing shield which can be peeled off to prevent the indentation of writing to accidentally carry through onto further sets. An optional extra for pads is the handy Attached "Hinged Writing Shield" which is attached to the pad and functions in the same way as a standard loose writing shield.
Pads are mostly found in an office environment as they are not quite as durable as NCR Book would be.
NCR Books - What are they?
NCR Books work in a similar way to how a carbonless NCR Pad does except that the Sets are bound into the Book and work more like how a cheque book would. Each page is perforated from a minimum of 15mm (25mm preferred!) from the bound edge and thus will leave a "stub" in the spine. The bottom copy of each set can also remain ["fast"] in the book if specifically required, however the perforations are quite strong nowadays so we normally"Crash Perf" as standard, meaning we sequentially number and perforate down through all the sheets of each Set in just one pass within our Finishing dept.
Carbonless NCR Books are the most durable and hard-wearing NCR product possible due to their robust spine, durable straw-board back and white card cover which protects the important areas of the Sets inside. Their most common usage would be on-the-road with delivery drivers, construction sites, with Tradesmen, or anywhere they might get thrown around and abused a lot.