Within any printed document there are 3 critical areas we need to be aware of and keep our eyes on. Knowing these 3 areas are critical to ensuring our designs print the way we intend.

The Trim Area

The Trim Area is the physical size of the page or document. During the printing process, this is the area that is "trimmed" to produce the final page size.

The Live Area

The Live area is the region within a page that all of your copy and important elements must live inside of in order to ensure that they are no compromised in any way during the printing process. IN Illustrator, this is simple to set; just create a rectangle to the size of the intended live area, center it on your page, and "Make Guides" of that rectangle.   In InDesign it is a little more involved (ironicly). Here, you need to set the Margins of the page to the correct width to produce the correct live area. You do this by doing a little math.  If we have a document that is 8 1/2 x 11" trim and 7 x 10" live area, we will take the Trim width, subtract the Live width & divide that by 2 (because we have 2 margins: left & right) so the formula is "Trim Width - Live width / 2" We then do the same with our height.  It is a good practice to always figure the left & right & top & bottom seperately as they do not always match.

The Bleed Area

The Bleed areas is the area beyond the trim that all elements must be extended to that you intend to run to the very edge of a page.  Generally set to 1/8" it is intended to ensure that, should the sheet shift during printing, you don't end up with an unsightly white line running down the edge of the page.