MNI Blog  /  3 minute read

What Do Cookies Do for Digital Marketers?

At MNI, we pride ourselves on being audience strategists. We can identify even the most niche audiences that our clients are looking for, and target them specifically using our proven


Consumer Targeting 101


At MNI, we pride ourselves on being audience strategists. We can identify even the most niche audiences that our clients are looking for, and target them specifically using our proven digital and print solutions.
Cookies are one of the many tools we use.

What Do Cookies Do?

Cookies are small pieces of code that are added to users’ web browsers as they visit different websites. The information they contain delivers a more customized user experience, as it remembers previous internet actions, like log-in information, location settings, what’s in your cart, and more. Advertisers use cookies to collect data—like what websites you visited—that will help them deliver the most relevant and targeted content to specific audiences.


How does online advertising work?

Because we live and breathe consumer/audience targeting every day, it’s easy to forget that it’s a complicated process. Doing it well involves the most cutting-edge technology, comprehensive data analysis, and hands-on expertise from a seasoned team of media and marketing experts. Check. Check. And check.

As a media targeting company, making sure our clients fully understand the process is key to our success. It helps them make informed decisions about their plans and campaigns and be able to communicate their goals clearly. With that in mind, below is a very top-line description of two ways digital consumer targeting works: by device ID and cookies.


How to target customers online using cookies

Cross-device tracking by Device ID

With Device ID targeting, marketers can zero-in on specific mobile devices,
including smartphones, iPads, laptops, desktops, or smart TVs. Here’s how:

What is a Device ID?

A device ID is a unique code that’s given to mobile devices by their manufacturers. Advertisers can use these identifiers to accurately target specific devices.

Since a device ID is permanently tied to a specific device, it’s a more efficient way of targeting. By using device IDs, advertisers can target mobile and other connected devices more precisely, and gather all-important data not just from the web, but also across all mobile activity. Device IDs allow for cross-device targeting, and let advertisers seamlessly target ads to one person across all of their devices.  When you purchase a device, it’s registered to you based on subscription information you are entering into it—your carrier information for a phone, your Netflix account information on TV, etc. This information is strung together to determine it’s still you, easily switching from device to device. This is also called deterministic targeting, which means there is a true link between a user and their device(s).



Retargeting through third-party cookies

With cookie targeting, marketers target consumers by their past behavior online—what sites they visited,
what items they looked at, what purchases were made, and more. Here’s how:


What are tracking cookies used for?

A tracking cookie is a small string of text that gets added to the user’s web browser (Firefox, Safari, Chrome, etc.) when they visit certain websites. The code is stored in the user’s browser over a period of time set by its creators (or until the user deletes it), and changes the way the browser interacts with certain pages. The data that the cookie collects from the browser is stored on the websites the user visits. Third-party cookie technology is used to facilitate various functions for online advertisers, including

• Activating retargeting ads—more on that later

• Storing data (e.g., the items you’ve added to your shopping cart on an ecommerce site)

• Retaining data previously entered into forms (used for autocomplete functions, like name, address, phone, etc.)

• Saving user preferences

• Authentication: Cookies communicate the user’s account details and log-in status to account-protected servers—which sites you are logging into and using

• Recording user activity

Cookies make online activity easier for consumers by recognizing user behavior—it’s like walking into your local diner, and the waiter knows you’re a vegetarian and that you don’t like green onions in your home fries. Cookies tailor your online experience.


What do Cookies Store?

Note that most cookies don’t contain any personal information like your name, email address, or phone number. Some of the data cookies collect includes your

• Age

• Gender

• Location

• Interests

• Behavior on your website or on search engines

Advertisers use cookies to keep track of which ads you’ve been served (more specifically which ads your browser has been exposed to).


A Real World Example of How Retargeting Ads Work

I use my mobile phone to browse Data is collected as I place items in my cart: diapers, toys, size 8 boys football gloves, size 10 boys football gloves, and adult ski gloves. Voila, I’ve been identified as a likely mom with kids, whose family is active outdoors. Marketers can—and do—retarget me with coupons and reminders from my favorite stores.

Next, I’m on my iPad. Companies ‘know’ it’s still me because I have registration info entered. My iPad includes a real estate app that I’m checking frequently. Marketers can assume I’m a potential new homebuyer. I also have a lot of recipe apps.  And I recently booked a trip online for six people in my family. My online activity is starting to paint a very clear picture of who I am!

I go to the grocery store later and use my Shopkick app for purchases. More data is gathered about my grocery habits and it’s clear that we’re a healthy-ish household, and occasionally indulge.  We’re great targets for yogurt, hummus, ground turkey, and sometimes Ben & Jerry’s Phish Food Ice Cream.

Consumer targeting is the backbone of successful campaigns. It helps brands by ensuring that their ad dollars are working as hard as they can, reaching precise audiences with ads that are relevant to them. It’s also helpful to consumers, who get a more custom and personalized online experience.

Read more from our ad experts on similar topics like cross-device targeting and micro-targeting.