Editing PostScript (section)

=== Before PostScript ===
Prior to the introduction of [[Interpress]] and PostScript, printers were designed to print character output given the text&mdash;typically in [[ASCII]]&mdash;as input.{{citation needed|date=January 2023}} There were a number of technologies for this task, but most shared the property that the [[glyph]]s were physically difficult to change, as they were stamped onto [[typewriter]] keys, bands of metal, or optical plates.

This changed to some degree with the increasing popularity of [[dot matrix printer]]s. The characters on these systems were drawn as a series of dots, as defined by a [[typeface|font]] table inside the printer. As they grew in sophistication, dot matrix printers started including several built-in fonts from which the user could select, and some models allowed users to upload their own custom glyphs into the printer.

Dot matrix printers also introduced the ability to print [[raster graphics]].<ref>{{Cite web |title=Dot-Matrix Graphics |url=https://www.ibm.com/docs/en/zos/2.4.0?topic=capabilities-dot-matrix-graphics |access-date=2025-03-04 |website=www.ibm.com |language=en-us}}</ref> The graphics were interpreted by the computer and sent as a series of dots to the printer using a series of [[escape sequence]]s. These [[printer control language]]s varied from printer to printer, requiring program authors to create numerous [[device driver|drivers]].

[[Vector graphics]] printing was left to special-purpose devices, called [[plotter]]s. Almost all plotters shared a common command language, [[HPGL]], but were of limited use for anything other than printing graphics. In addition, they tended to be expensive and slow, and thus rare.