Anatomy Of A Spec Sheet

You can imagine my panic when I received something similar to this (though without the handwriting explaining everything..) on my first job. The crop marks were particularly puzzling. What did they mean? How big is the art supposed to be? What are those codes? I of course had to call up my agent and have them walk me through everything. I was quite the green horn. So above is a copy of the spec sheet from my recent job (a spec sheet is created by the art director to guide the artist through the illustration process - it contains all needed info such as sizing, art placement and directorial instructions of what they want within the illustrations themselves.) I've hand-written in what each part means.

Crop marks - Marks that show where the pages of the book will be cut/cropped.
Bleed marks - Marks that show where the art should bleed to. In other words, when art goes off the edge of the page of a book, you create the art usually about 1/4" larger than the edge of the page. Then they slice off the extra.
Reference # - Each art piece has a reference number. Art directors receive hundreds of pieces of art in the mail. This helps with keeping track of art for records, and keeps art from getting misplaced or lost in the wrong pile.

This is a different piece of art from the spec description, but it's from the same book. Oh and by the way, don't run your sailboat up on the sand like this (LOL). I was told to draw the boat up on the bank. Not a good thing in real life.