Many of you today use printer by their own without much without really understanding file formats. Whether in the context of your work, for your personal impressions, or just to send us files, it is necessary to understand some basic principles.

For all your communication paper, remember to observe the following points:

> Files minimum resolution 300dpi (or 300 ppp)
> CMYK color mode (and not RVB)
> 3 mm lost on border surrounding your document, which must contain the background and visual located within 5 mm of the cut that should be overflowing.
> Marge of error 5 mm : no significant element (texts …) should be in this internal peripheral area of your document.
DPI

What is DPI?
The DPI resolution is a measurement unit. Dots per inch.
The more dots per inch, the better the resolution of the image will be.
The computer screen usually has a display resolution of 72 dpi in its basic definition, (but this can change depending on the user settings), while a printer must be at least 300 dpi to paper .
Therefore, a correct image that appears on a computer screen will be much less defined in print.

CMJN / RGB

The mode CMJN (Cyan, Magenta, Jaune, Noir)

RGB  (Red, Green, Blue) is the default colour mode used on computer monitors and is not suitable for printing.
This mode assigns an intensity value to each pixel.

Small point of caution: all images you can find on the internet are not royalty free and some are licensed. So be sure to observe the copyright.
Also make sure that imagines are of sufficient size, so check that they conform to 300 dpi resolution.