Plotter Languages collects practical CAD plotting guidance for this topic within Printers & Plotters. Use these articles for setup, verification, troubleshooting and reliable final output.
HP-GL/2 is a technical plotting language with deep CAD history, but the generic AutoCAD HP-GL/2 driver is not the default choice for every modern plotter—especially modern HP DesignJets.
PostScript is a page-description/rendering path supported by some large-format devices and production workflows. It can be valuable, but it should be chosen because the exact plotter supports it and your test sheets benefit—not because it sounds more ‘professional.’