Page properties are massively important for any media companies and they must meet the tight
guidelines set for either on screen or for print and they are both widely different within size and pixel dimensions.
For screen
The standard settings for screen / mobile or any more portable devises are :
1064 x 475 Pixels (these sizes are set by the Internal advertising bureau ) ( http://www.iab.net)
Items for print should always be in Pixels which stands for ( Picture Element) .
The standard size the screen resolution also set by the IAB is 72 Pixels this is ever changing as mobile / portable devices are becoming more and more advance but to date this is still the average set resolution for screen.
the colour mode used is Vital as on screen not many colours are needed and it also makes are far smaller file format which is ideal for screen promotions or web banners / buttons . The required mode is RGB ( Red Green , Blue ) and this give us the equal colours which give the document the white light we need for screen.
Items for print
The items for print are slightly different and somewhat more advance but are simple to create using programmes such as Adobe Photoshop etc.
using the present settings on Photoshop their is a setting called International Paper , which is the ideal size of A4 !
You must also be using 300 Pixels for resolution as this gives the best quality when printing items for promo purposes and also ensuring that you use the guidelines of size of approx 216 x 303 Pixels .
their is an added 3mm added to each edge of the paper for something called the Bleed which is vital as the image will be printed to edge giving you no White Lines.
the colour format must be RGB whilst creating the document for print and then changed to CMYK for the ultra glossy look when printing items to give the professional look .
As for the Bleed you will need to go into the ruler settings and set the bleed up which is 3mm from each edge on the top , bottom , and both edges . and also set a 10mm safety rule to give the image the best look.
in all the image properties are vastly important in the interactive industry for the best outcome all guidelines must be met.