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Ever wondered how your favorite apps like Snapchat or Instagram work their magic? It might seem like a world of complex code, but many of the core ideas behind them are surprisingly straightforward. Let's explore three essential concepts that drive these apps: algorithms, APIs, and A/B tests.

Algorithms are at the heart of every piece of software, from classic games like Pac-Man to modern apps like Facebook. These are well-defined procedures that help computers solve problems. Take Spotify’s algorithm, which uses a technique called collaborative filtering to recommend songs. The process involves analyzing your music preferences and comparing them with the playlists of millions of other users. Say you love The Beatles, and several playlists featuring The Beatles also include songs by The Rolling Stones. Spotify might assume there’s a thematic connection and, lo and behold, it will probably start suggesting Rolling Stones songs to you.

In today’s world, the phrase “there’s an app for that” reflects a booming app economy. In 2016, it was valued at over $50 billion in total, and that number is only going up. This app economy operates on principles vastly different from traditional models.

Unlike traditional goods, which are sold for a price, most apps are free to download. Yet the companies behind some apps are worth millions, even billions, of dollars. This illustrates how the “freemium” model works, where basic services are free but advanced features cost money. For example, the app Candy Crush is free to download but offers in-app purchases for extra “lives” or levels. Similarly, Tinder provides limited swipes for free, with unlimited access available for a monthly fee. This model thrives on user engagement: the more invested a user becomes, the more likely they are to pay for premium features.

Back in 2006, Alaska Senator Ted Stevens misdescribed the internet as “a series of tubes.” It was a funny gaff –⁠ but it also highlights the surprising difficulty of describing this tool many people use daily. How much do you know about how the internet works?

When you type “google.com” and hit enter, a complex process unfolds. Every webpage, like a building, has a unique address, known as a Uniform Resource Locator. This URL ensures that anyone who types it in will arrive at the same destination.

On the internet, every click, purchase, and interaction contributes to an ever-growing digital universe. This realm, known as “big data,” is expanding at an astonishing rate. As Google co-founder Eric Schmidt noted in 2010, we now create as much information in two days as we did from the dawn of civilization until 2003. This massive volume of data, or five exabytes every two days, surpasses our traditional storage capacities and presents unique opportunities and challenges.

A classic example of big data’s power is Target’s prediction of a teen’s pregnancy. In 2012, a father in Minnesota discovered a catalog in the mail that contained maternity products – and it was addressed to his daughter. Outraged at the implication, he confronted the store manager and accused Target of encouraging his teen daughter to become pregnant. However, a few days later, the father called Target back with an apology. After a conversation with his daughter, he had learned that she was indeed pregnant.

The internet is a symbol of both limitless potential and contentious debates over control, privacy, and freedom. This reality is shaped by ongoing policy battles and legal discussions, which significantly affect technology’s role in society. 

At the heart of these debates are the Internet Service Providers, like Comcast, AT&T, and Verizon. These giants not only connect us to the internet but also hold the power to track our every online move. The contentious issue here is the selling of our browsing history to advertisers, a practice that has traveled along a regulatory rollercoaster. In the United States, this practice was restricted by the Federal Communications Commission in 2016. However, those protections were overturned just a year later, allowing Internet Service Providers to sell user data without consent. This move sparked outrage, highlighting the fragile balance between consumer rights and corporate interests.