I’ve heard the term used in two ways…
One would refer to using a Pantone or otherwise spot color (Window / Swatches / (Click the drop-down arrow) Open Swatch Library / Color Books / Pantone Solid Coated or whatever).
They you’d pick one color swatch. You’d use that color swatch to color everything in your art. Then you would set the different color values for your components using the slider in the Color palette.
When using spot colors, printers are able to create a single plate that can print one color ink that will be screened to different values.
Another, more involved, way would be to use screen patterns, (Window / Swatches / (Click the drop-down arrow) Open Swatch Library / Patterns / Basic… / Dots, Lines or whatever.
Then you would use these patters to effectively build your own screens. This can be time consuming. It’s potentially a much more involved process, but you would have total control.
Vince
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