Glossary

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Advanced print technical guidelines
Advanced web technical guidelines
Frequently Asked Questions

What is…

Ad Unit
An ad unit is a web advertising slot positionned on a website and designed to accept ad creatives with a predetermined set of characteristics : pixel size, maximum file weight, animation length, etc. Our ad units follow the industry standards established by the Internet Advertising Bureau.

Campaign
An advertising campaign typically refers to a series of advertising messages that share a single idea and theme. An advertising campaign may include print and web advertising and use one or many creatives.

CMYK
CMYK refers to the four types of pigments (Cyan, Magenta, Yellow and Black) used to create print images. By combining the pigments in different amounts and proportions, we can create a whole range of colours. CMYK is a “subtractive” colour mode, because it starts with a white object (the blank piece of paper, which reflects white light) and then masks the brightness with pigments until the desired color is attained. When we cover the page completely until it becomes all black, we can say that we’ve removed (subtracted) all of the colour; the paper can no longer reflect light.

Because this method is very different from the way computer monitors create colour (see: What is RGB?), a printed image will always look somewhat different from the way the original file looked on your computer. To get the best results out of our newspress, please consult our Colour section.

Colour profile (ICC)
A colour profile is a set of data that characterizes a colour input/output device, according to standards promulgated by an organization called the International Color Consortium (ICC). The profile describes the way the device understands and manipulates colour, so that when two devices communicate colour data to one another, the results look the same visually.

If your computer monitor shows you certain colors, but cannot communicate them properly to our newspress, or if our newspress cannot accurately translate them to ink colours, you may be disappointed to see that the colours of the printed product are not very close to what you saw on your monitor. Just like you would expect of multiple audio or video conversions, the more profile conversions occur, the more colour information will be lost in translation.

For this reason, when we know what device we wish to communicate colour information to, it’s important to work from the correct ICC profile; either the final profile, or one which is highly compatible with it so that minimal loss occurs. See: Which colour profile should I use? To learn how to assign profiles in specific applications, please see our Special Guidelines for Illustrator, Photoshop and InDesign.

CPD
CPD stands for cost per day, and is a way of calculating the cost or value of web advertising campaigns. If you purchase advertising at 16$ CPD, you will be charged 16$ per day for the duration of the campaign, regardless of how many impressions are delivered. As opposed to CPM (cost per thousand impressions) campaigns, CPD campaigns aim to deliver as many impressions as possible during a set period of time.

CPM
CPM stands for cost per thousand (impressions), and is a way of calculating the cost or value of web advertising campaigns. If you purchase advertising at 25$ CPM, you will be charged 25$ for every thousand impressions delivered during the campaign. As opposed to CPD (cost per day) campaigns, CPM campaigns aim to reach a fixed number of impressions during a flexible time frame.

Creative
A creative is a print or web-ready file, created by a graphic designer as part of an advertising campaign. The term “ad material” refers to original files and elements of a creative which require assembly or adjustments prior to being displayed. Due to the specific adjustments required for newsprint, print creatives are often referred to as “ad material” despite being considered print-ready.

CTR
CTR (click-through rate) represents the percentage of clicks on an ad creative per impressions delivered. It is used to compare the success of various creatives within a web advertising campaign. Since the number is typically quite low (0.2 to 0.3% according to iMedia Connection (2010)), we do not recommend using CTR to measure of the overall success of a web campaign.

DPI
DPI stands for “dot per inch”. Whether it is printed on paper or displayed on your computer screen, a picture is made up of tiny little dots. Resolution is measured by the number of dots in a horizontal or vertical inch. Like any other device, your computer monitor has a maximum number of dots it can process and display in a defined area, regardless of how much dot information the file contains. For computer monitors, that limit varies between 72 and 100 dots per inch. This represents the “low resolution” range. Even if your file contains 300 dots’ worth of picture information per inch, your monitor cannot display them. This is why you can’t tell if a file is high resolution simply by glancing at your monitor, and why most of the files you find on the Web will be in “low resolution”. Most printers, however, print a minimum of 300 dots’ worth of information per inch of paper.

Naturally, a “low resolution” file will look much smaller on paper than it did on the computer monitor. Why? Because while 72 dots took up 1 inch of space on computer monitor, they only take about 1/4 of an inch on paper.On the other hand, if you try to force your 300 dpi capacity printer to print the image in the size you want, it will have to invent dot information in order to fill in the blanks. What we end up with is a blurry picture, as we only provided 72 dots’ worth of information for each inch of picture; the printer had to guess what the remaining 228 dots should look like!

So why don’t we just use the highest possible resolution all the time? For one, it’s useless to provide more than 300 dpi’s worth of information to your printer, as it will simply discard the extra information. Perhaps more importantly, the more dot information your file contains, the largest (or heavier) it becomes, requiring more storage and longer transfer times. With the press we use, 300 dpi is your best bet. We recommend leaving your web ads at 72 dpi, however.

Dot gain
Dot gain is a print defect due to the blotting properties of paper. It causes an increase in the size of halftone dots, leading to luminosity loss. Think of the image being sent to the press as a matrix of little dots, all neatly aligned, perfectly circular and even in size. When we print it, the texture and absorbency of the newspaper, the fluidity of the ink and the squishing of materials together all contribute to distorting, blurring and enlarging the dot. With less white space between the dots, the image appears darker or more contrasted to the human eye. Dot gain correction is a largely handled by colour profiles.

Embedding (for fonts and images)
To help reduce file sizes, graphic design software have a tendency to link to external content rather than embedding it (creating a copy of it within the file). This can be practical as long you open the file on your own computer; the program will go fetch the images and fonts that you need as you need them, and the file itself will be lighter. If you try to open the same file on someone else’s computer however, those bits and pieces which were external to the file will be missing.

This leaves you with two options: either track down and send all of the images and font files to the other person directly, or embed them into your file. What we recommend depends on which program you use, and whether we will have to remake your file from scratch or not. Please refer to our Special Guidelines for more information.

Fold
“Above the fold,” a term borrowed from print media, refers to a web ad that is viewable as soon as the page loads, such that the user doesn’t need to scroll in any direction. Display resolution affects what is immediately viewable. On mcgilldaily.com and delitfrancais.com, the Leaderboard and top Bigbox are considered to be above the fold.

Impression
Impressions are a measure how many times an specific ad was displayed on a website. Impressions will not register if a user clicks away from a page before the ad has a chance to load, or if the ad does not load for any other reason (unsupported format, blocked images, etc.) Impressions are tracked by the software or system through which the ads are served, and are used in the web advertising industry to determine available inventory and pricing (see : What is CPM?) as well as evaluate the performance of a campaign.

Insertion Order (IO)
An insertion order is an authorization to print an advertisement. It includes all of the instructions pertaining to your ad, including publication dates, size of ad, positioning, number of print insertions, days of web display, etc.

Inventory
The inventory is the total number of ad impressions that a website is able to deliver in a set period of time. “Available inventory” for a particular ad unit refers to amount of inventory that hasn’t already been reserved by previously booked web campaigns.

Overprint
An overprint is a layer of ink that goes on top of another layer, creating a blend of colours. By default, when you stack two objects, the one on top will “knock out” the colour underneath it, so that only the colour of the top object gets printed. It keeps the colour distinct from one another, though small gaps or overlays sometimes occur due to slightly misaligned colour plates. If you’re concerned about white gaps and do not want to set your colours to blend, please see: What does Trapping mean? To control overprints and trapping in Illustrator, please see our special Illustrator guidelines.

Pageview
Pageviews are a measure how many times a website’s page was displayed in a set period of time. One pageview is counted for every request sent to load a single HTML file. Pageviews differ from “hits”, which are counted when any type of file is requested (including images and other media, stylesheets, etc.) Pageviews are closely related to impressions.

RGB
RGB refers to three colored light beams (one Red, one Green, and one Blue) which can be superimposed to create a whole range of colours (just like the colour changes when spotlights are crossed and uncrossed at music shows). Those three primary colours correspond to the three types of cone cells in human eyes. This way of creating colours directly from light beams (rather than by combining pigments, as in paintings, or the inks your printer uses) is especially used in TV screens and computer monitors.

We call the RGB colour mode “additive” colour mode since we start out with a black monitor (all lights are turned off) and can progressively add more light to get brighter and brighter colours, up until it’s fully white. Since computers fire light beams at your eyes, they are able to create much brighter colours than we are able to reproduce on paper. This is why images that are meant to be seen on the computer look their best when they are in “RGB mode”. See also: What is CMYK?.

Resolution
The resolution of a file is the density of the picture information which it contains. That information appears in the form of pixels (on your computer monitor) or dots (on paper). As a general rule (and up to a certain point), the more information is contained in a defined area, the sharper the image will appear. Image resolution is generally calculated in DPI (dots per inch). A high resolution image contains more dots in one inch of vertical or horizontal space than a low resolution image does. See DPI for more information.

Rich black
Rich black is simply black ink mixed with a bit of cyan. The bluish hue is not very noticeable, but serves to make the black appear less flat. You can find our recipe for rich black here.

Serif, Sans and Sans-Serif
A Serif font has semi-structural details on the ends of its characters, called serifs (ex. Times). A Sans-Serif font (often just called “Sans”) is simply a font which doesn’t use serifs (ex. Arial).

TAC limit (ink %)
TAC stands for Total Area Coverage. The TAC limit is the maximum amount of ink which can be pressed onto a single area of the paper without causing bleeding. To understand what the percentage stands for, select a CMYK object and take a look at its colour values. You will see that the value for each colour is expressed as a percentage. Assigning a Cyan value of 100% to an object doesn’t mean that it contains only Cyan, but rather that the entire volume of Cyan ink which we are allowed to use on this area of the paper will be used.

Of course, if we were to set every colour value to 100%, we would end up with way too much ink on our sheet; the paper could not absorb it and the ink would run everywhere. To avoid this kind of scenario, it’s important to know your printer’s TAC limit, which is the limit that the sum of the colour values must not exceed. Consult our Ink Coverage section for more information.

Targeting
Targeting adds criteria to your web advertising campaign to match the audience with the campaign’s objectives. Campaigns may be targeted geographically, by user language, browser, device or operating system.

Trapping
Trapping is a method used in newsprint to avoid misalignment or gaps between the different colours. It creates fine overlaps between the different colours. For information on how to set trapping, please consult our Special Guidelines for Illustrator.

Unique visitors
A unique visitor is someone with a unique IP address who is entering a website for the first time that day. Thus, a visitor that returns within the same day is not counted twice. A unique visitors count gives a general indication how many different people are part of the site’s audience. Note that dynamic IP addresses, disabled cookies, and other situations may prevent unique visitors tracking to function properly.

Vector
Vector images and fonts are created using mathematical expressions such as points, lines, curves, and shapes or polygons, rather than the traditional dot/pixel matrix system. This allows the shapes to be modified (and even scaled to any size) without losing any definition. We encourage you to use vector elements whenever possible, as they are independent of file resolution constraints.