In sewing and fashion design, a pattern is the template from which the parts of a garment are traced onto fabric before being cut out and assembled. Patterns are usually made of paper, and are sometimes made of sturdier materials like paperboard or cardboard if they need to be more robust to withstand repeated use. The process of changing the size of a finished pattern is called grading.
Markers are a guide used in the cutting process. It is long sheet of bond paper with all of the pattern pieces used to make a style laid out in a configuration intended to reduce fabric waste as much as is possible, including all of the sizes you’d need of a given style. Markers are often made by computer and printed out with a plotter. The marker is laid on top of the fabric layers which cutters then use to cut out all of the pieces at once.