Ask An Expert: Are Internet Cookies Dangerous?

BU Experts
4 min readMay 26, 2023


Digital marketing expert shares his thoughts on online display advertising, browser cookies, online privacy, Europe’s GDPR, and the post-cookie future of the web.

By Katherine Gianni

Internet cookies.

Unlike chocolate chip confections we’re used to thinking of when hearing the word 🍪, these cookies are small blocks of data created by a web server while a user is browsing a website. Internet cookies have been known to conjure up some unsavory feelings — with many folks wondering if allowing or accepting them could lead to cyberattacks or stolen data. In a recent Reddit Ask Me Anything (AMA), digital marketing expert and Boston University Questrom School of Business Assistant Professor Garrett Johnson addressed these concerns and other topics related to online privacy and display advertising.

Professor Johnson’s research is threefold — focusing specifically on internet marketing, digital ad effectiveness, and privacy. His analysis of Internet marketing examines online display advertising: the medium’s effectiveness and privacy issues. His ad effectiveness research uses large-scale experiments to measure how and how much ads work. Finally, his privacy research quantifies the value of online behavioral targeting to industry and considers the impact of policy & self-regulatory approaches. Professor Johnson works with Internet companies — including Google and Yahoo! — to answer these questions with Internet-scale data. The takeaways from his Reddit AMA are useful in debunking common misconceptions around cookies, understanding the role of ad blockers, and examining the future of digital marketing.

Photo by Firmbee on Unsplash.

1) So…what exactly are Internet or browser cookies?

Professor Johnson defines the term are how they’re most commonly used across the web.

2) Accepting vs. rejecting cookies will lead to different outcomes.

When clicking into a new app or website, it’s common to be confronted with a pop-up asking to “accept or reject all cookies.” Professor Johnson shares how each choice can impact our browsing experience.

3) Browser cookies can trigger uneasiness…but you don’t have to fear them.

Worried that accepting cookies will lead to data privacy concerns? Professor Johnson assures that the risk is low.

4) Ad blockers may actually be increasing ad effectiveness.

While it may sound counterintuitive, experts point to reasons why this software is helping — not harming — the digital advertising business.

5) Nuisance advertising is likely here to stay.

Ever had a pop-up disrupt your Internet browsing? Or, a video ad begin to autoplay as soon as you click on a new website link? Both are examples of nuisance advertising. Professor Johnson explains why this type of content — albeit irritating to most users — isn’t going anywhere.

6) Not all digital marketing certifications are created equal.

Professor Johnson shares some of his top recommendations for online certificate programs.

7) Generative AI may serve as a useful tool to enhance digital marketing.

From content generation to improving marketing automation, there are multiple ways marketers are already using the technology to their advantage.

8) Online advertising effectiveness should be measured by experiments.

Professor Johnson describes some of his research methods to determine how successful certain digital marketing/ad campaigns actually are.

For additional commentary by Boston University experts, follow us on Twitter at @BUexperts. Follow Professor Johnson on Twitter at @garjoh_canuck. For research, thought leadership, and information from Boston University’s Questrom School of Business and Hariri Institute for Computing, follow @BUQuestrom and @BU_Computing.



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