Dividing generations by abstract dates might seem senseless, but the first generational terminology was born from the baby boom post-World War II. After the war, birth rates across the world spiked; between 1946 and 1965, 77 million babies were born in the United States alone according to data collected by the Pew Research Center.

After a sharp drop-off in birth rates in 1965, researchers classified babies born during that period as Baby Boomers.

The next generation, Generation X, started in 1965 but didn’t have as clean of a cutoff; most researches typically cut Gen X off at 1980, though some classify Gen X through 1984.

Then came Millennials. Typically regarded as those born between 1980 and 1996, Millennials are defined by growing up in the Internet Age, and the generation has experienced the largest variety of social and economic conditions thus far, according the Pew.

Though young people are often widely referred to as Millennials, the reality is that most people starting college now aren’t Millennials but part of Generation Z; kids in Generation Z were born between 1995 and 2010 and, therefore, make up most of the freshmen demographic.

According to Chuck Underwood, the founder of a generational consulting firm, Gen Z does not exist yet. Technically, a new generation comes of age when they can vote, and the majority of Gen Z cannot yet do so.

Like Generation X, Millennials don’t have a specific birthdate cutoff. However, Millennials and Gen Zers are defined and divided by drastically different life events, which shaped the separate generations.

Millennials were between the ages of 5 and 20 when the 9/11 terrorist attacks shattered the nation and were generally old enough to understand the significance of that moment. Most members of Gen Z either don’t remember the event or hadn’t been born yet.

As a result of the attacks, Millennials grew up in the shadow of the wars in Iraq and Afghanistan, which sharply divided the nation and contributed heavily to the intense political polarization that shapes the current political environment.

Millennials were teenagers or young adults during the 2008 election, and they contributed mightily to the youth vote that helped elect the first black president.

Beyond politics, the majority of Millennials entered the workforce during an economic recession. As a result, Millennials’ life choices and attitudes have been shaped by the recession in a way that those in Gen Z have not.

The way Millennials interact and communicate with the world around them is another defining feature. Baby Boomers grew up as the television industry expanded, Generation X saw the computer revolution take shape and Millennials came of age during the explosion of the internet.

What makes Gen Z unique is that all of the above have been part of their lives from the start. The first iPhone came out in 2007, when the oldest Gen Zers were ten. The primary means of communication for Gen Z have been mobile devices and the internet. Millennials had to adapt to social media and constant connectivity; Gen Z grew up with both as the norm.

The implications for Gen Zers having to constantly perform on social media are not totally defined yet. Recent research has shown youth behaviors have shifted dramatically from generations past, in both positive and negative aspects, but as some Gen Zers are as young as ten, only time will tell how the Connected Age impacts youth development.

As the 2008 election shaped the political landscape for Millennials, so did the 2016 election for Generation Z. For many, Donald Trump is the first U.S. president they’ve ever known. The contrast between George W. Bush and Barack Obama formed the political debate for Millennials. The current political environment may have similar effects on Gen Zers.

The Columbine shooting in 1999 shocked Millennials and the nation; the effects of that shooting are still rippling through the U.S. today. For Generation Z, gun violence in schools is the status quo. Nobody claims to be shocked by mass shootings anymore. How can we be surprised when there were more mass shootings than days of the year in 2019?

Millennials paved the way for Generation Z to take the mantle and disrupt national conversation about our youth.

As the past several years have shown, Generation Z can mobilize. Five million youths marched to protest gun violence. They are not limited by local events or even national events. Widespread connectivity gives the new generation access to global events and crises, which led to millions of young people marching to protest climate change.

Recent research has shown that as adults, Millennials are forging a distinct path. They are idealistic and confrontational. Thanks in large part to Generation X, they are selfish and entitled. They are confident and assertive. They are generally unattached to organized religion, linked together by social media, burdened by debt, distrustful of politics, in no rush to marry and largely unable to afford the white picket fence and two cars that their parents had.

Still, Millennials are optimistic for the future. They vote. They have a higher life expectancy than any previous generation.

Meanwhile, still growing up, Generation Z unites behind the search for truth. They value individualism and avoid labels. They mobilize quickly and effectively for a variety of causes. They believe profoundly in their individual ability to solve conflicts and improve the state of the world.

Gen Zers don’t just tolerate diversity — they expect it. They are accepting of gender and sexual identity. They’ve lost some of the optimism from the Millennial generation. They are less idealistic and less hopeful for economic prosperity.

Generation Z is widely considered to have cut off in 2010, meaning children being born today are part of a whole new generation. Though they’ve yet to be named, researchers estimate that they will be the most formally-educated generation and most technology-supplied generation ever. In time, we’ll understand the national and global events that will shape their worldview.

For now, we watch Generation Z take their first steps into adulthood, taking the torch from the Millennials before them.