Prepress Terms Explained for Print Buyers

Prepress is the stage between submitting artwork and actual printing. Knowing prepress terminology helps you understand what’s happening behind the scenes and ensures files are print-ready.

Here are some key prepress terms to know:

• Preflight – The process of checking files for errors (missing fonts, low resolution, etc.) before printing.

• Proof – A test print or digital file for approval before production.

• Bleed – Extra image area that extends beyond trim size to avoid white edges.

• Crop Marks – Small lines showing where the piece should be trimmed.

• Imposition – Arranging multiple pages on a sheet for efficient printing and proper page order.

• Trapping – Slight overlapping of colors to prevent gaps caused by misregistration.

• Knockout – An area of one color left blank so another color can print on top.

• Overprint – Printing one color directly on top of another.

• Rich Black – A mix of black ink plus other colors (like cyan or magenta) to produce a deeper black.

• Vector vs. Raster – Vector graphics use points and paths (scalable), while raster images use pixels (resolution-dependent).

• Halftone – An image created using tiny dots of varying size and spacing to simulate shades.

• Line Screen (LPI) – The number of halftone lines per inch; determines image sharpness in print.

Why It Helps to Know These

Learning prepress terms helps you prepare files correctly, reduce costly delays, and feel more confident when reviewing proofs or approving jobs. A little knowledge goes a long way in making sure your project moves smoothly from design to final print.

Need help with your next project? Contact AV Graphics for expert prepress support and end-to-end printing and packaging services.